PlzNavigate: Speculatively spawns a renderer process for navigations.

content/browser/frame_host/navigator_impl_unittest.cc

Index: content/browser/frame_host/navigator_impl_unittest.cc
diff --git a/content/browser/frame_host/navigator_impl_unittest.cc b/content/browser/frame_host/navigator_impl_unittest.cc
index 2258b258559dae276adc48b300c29e3e03836a22..f3f684199d7e4295c40b08444928d56147d4cb4d 100644
--- a/content/browser/frame_host/navigator_impl_unittest.cc
+++ b/content/browser/frame_host/navigator_impl_unittest.cc
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include "base/command_line.h"
 #include "base/macros.h"
 #include "base/time/time.h"
 #include "content/browser/frame_host/navigation_controller_impl.h"
@@ -15,6 +16,7 @@
 #include "content/browser/streams/stream.h"
 #include "content/common/navigation_params.h"
 #include "content/public/browser/stream_handle.h"
+#include "content/public/common/content_switches.h"
 #include "content/public/common/url_constants.h"
 #include "content/public/common/url_utils.h"
 #include "content/test/browser_side_navigation_test_utils.h"
@@ -73,8 +75,41 @@ class NavigatorTestWithBrowserSideNavigation
     return static_cast<NavigatorImpl*>(frame_tree_node->navigator())
         ->GetNavigationRequestForNodeForTesting(frame_tree_node);
   }
+
+  RenderFrameHost* GetSpeculativeRenderFrameHost(RenderFrameHostManager* rfhm) {
+    return rfhm->speculative_render_frame_host_.get();
+  }
+
+  FrameHostMsg_DidCommitProvisionalLoad_Params BuildSimpleDCPLParams(GURL url) {

[clamy, 2014/12/16 15:22:48]

This is actually a rewrite of some of the helper functions of
TestRenderFrameHost. I think you should be using
TestRenderFrameHost::SendNavigate instead of
TestRenderFrameHost::SendNavigateWithParams and a function to generate default
params.

[carlosk, 2014/12/19 04:27:14]

Done.

+    FrameHostMsg_DidCommitProvisionalLoad_Params params;
+    params.page_id = 1;
+    params.url = url;
+    params.was_within_same_page = false;
+    params.is_post = false;
+    params.post_id = -1;
+    params.page_state = PageState::CreateForTesting(url, false, 0, 0);
+    return params;
+  }
 };
 
+// PlzNavigate: Test final state after a complete navigation (to avoid repeating
+// this these checks).

[clamy, 2014/12/16 15:22:48]

Remove the extra this.

[carlosk, 2014/12/19 04:27:14]

Done.

+TEST_F(NavigatorTestWithBrowserSideNavigation, NavigationFinishedState) {
+  const GURL kUrl("http://chromium.org/");
+  contents()->NavigateAndCommit(kUrl);
+  ASSERT_TRUE(main_test_rfh());
+  RenderFrameHostManager* rfhm =
+      main_test_rfh()->frame_tree_node()->render_manager();
+  EXPECT_EQ(RenderFrameHostImpl::STATE_DEFAULT, main_test_rfh()->rfh_state());
+  EXPECT_EQ(SiteInstanceImpl::GetSiteForURL(browser_context(), kUrl),
+            main_test_rfh()->GetSiteInstance()->GetSiteURL());
+  // After a navigation is finished no speculative RenderFrameHost should
+  // exist.
+  EXPECT_FALSE(GetSpeculativeRenderFrameHost(rfhm));
+  // With PlzNavigate enabled a pending RenderFrameHost should never exist.
+  EXPECT_FALSE(rfhm->pending_frame_host());
+}
+
 // PlzNavigate: Test that a proper NavigationRequest is created by
 // BeginNavigation.
 // Note that all PlzNavigate methods on the browser side require the use of the
@@ -85,9 +120,10 @@ TEST_F(NavigatorTestWithBrowserSideNavigation, BeginNavigation) {
   const GURL kUrl3("http://www.gmail.com/");
 
   contents()->NavigateAndCommit(kUrl1);
+  FrameTreeNode* root = contents()->GetFrameTree()->root();
+  RenderFrameHostManager* root_rfhm = root->render_manager();
 
   // Add a subframe.
-  FrameTreeNode* root = contents()->GetFrameTree()->root();
   TestRenderFrameHost* subframe_rfh = static_cast<TestRenderFrameHost*>(
       contents()->GetFrameTree()->AddFrame(
           root, root->current_frame_host()->GetProcess()->GetID(), 14,
@@ -95,6 +131,9 @@ TEST_F(NavigatorTestWithBrowserSideNavigation, BeginNavigation) {
   EXPECT_TRUE(subframe_rfh);
 
   FrameTreeNode* subframe_node = subframe_rfh->frame_tree_node();
+  RenderFrameHostManager* subframe_rfhm = subframe_node->render_manager();
+  EXPECT_NE(root_rfhm, subframe_rfhm);
+
   SendRequestNavigation(subframe_rfh->frame_tree_node(), kUrl2);
   // There is no previous renderer in the subframe, so BeginNavigation is
   // handled already.
@@ -110,6 +149,16 @@ TEST_F(NavigatorTestWithBrowserSideNavigation, BeginNavigation) {
   EXPECT_FALSE(subframe_loader->request_info()->is_main_frame);
   EXPECT_TRUE(subframe_loader->request_info()->parent_is_main_frame);
 
+  // Subframe navigations should not create a speculative RenderFrameHost.
+  // (unless site-per-process is enabled).
+  EXPECT_FALSE(GetSpeculativeRenderFrameHost(root_rfhm));

[nasko, 2014/12/18 00:22:39]

nit: Move this check before the comment as it doesn't check subframes.

[carlosk, 2014/12/19 04:27:14]

Done.

+  if (base::CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kSitePerProcess)) {
+    EXPECT_TRUE(GetSpeculativeRenderFrameHost(subframe_rfhm));
+  } else {
+    EXPECT_FALSE(GetSpeculativeRenderFrameHost(subframe_rfhm));
+  }
+
   SendRequestNavigation(root, kUrl3);
   // Simulate a BeginNavigation IPC on the main frame.
   contents()->GetMainFrame()->SendBeginNavigationWithURL(kUrl3);
@@ -122,6 +171,16 @@ TEST_F(NavigatorTestWithBrowserSideNavigation, BeginNavigation) {
   EXPECT_EQ(kUrl3, main_loader->request_info()->first_party_for_cookies);
   EXPECT_TRUE(main_loader->request_info()->is_main_frame);
   EXPECT_FALSE(main_loader->request_info()->parent_is_main_frame);
+
+  // Main frame navigations to different sites should use a speculative
+  // RenderFrameHost.
+  EXPECT_TRUE(GetSpeculativeRenderFrameHost(root_rfhm));
+  if (base::CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kSitePerProcess)) {
+    EXPECT_TRUE(GetSpeculativeRenderFrameHost(subframe_rfhm));
+  } else {
+    EXPECT_FALSE(GetSpeculativeRenderFrameHost(subframe_rfhm));
+  }
 }
 
 // PlzNavigate: Test that RequestNavigation creates a NavigationRequest and that
@@ -130,12 +189,18 @@ TEST_F(NavigatorTestWithBrowserSideNavigation, NoLiveRenderer) {
   const GURL kUrl("http://www.google.com/");
 
   EXPECT_FALSE(main_test_rfh()->render_view_host()->IsRenderViewLive());
-  FrameTreeNode* node = main_test_rfh()->frame_tree_node();
+  RenderFrameHostImpl* rfh = main_test_rfh();
+  FrameTreeNode* node = rfh->frame_tree_node();
+  RenderFrameHostManager* rfhm = node->render_manager();
   SendRequestNavigation(node, kUrl);
-  NavigationRequest* main_request = GetNavigationRequestForFrameTreeNode(node);
+
   // A NavigationRequest should have been generated.
+  NavigationRequest* main_request = GetNavigationRequestForFrameTreeNode(node);
   EXPECT_TRUE(main_request != NULL);
-  RenderFrameHostImpl* rfh = main_test_rfh();
+
+  // As we're re-using the current RenderFrameHost, no speculative one should be
+  // created.
+  EXPECT_FALSE(GetSpeculativeRenderFrameHost(rfhm));
 
   // Now return the response without any redirects. This will cause the
   // navigation to commit at the same URL.
@@ -151,17 +216,16 @@ TEST_F(NavigatorTestWithBrowserSideNavigation, NoLiveRenderer) {
   EXPECT_TRUE(main_test_rfh()->render_view_host()->IsRenderViewLive());
 }
 
-// PlzNavigate: Test that commiting an HTTP 204 or HTTP 205 response cancels the
-// navigation.
+// PlzNavigate: Test that committing an HTTP 204 or HTTP 205 response cancels
+// the navigation.
 TEST_F(NavigatorTestWithBrowserSideNavigation, NoContent) {
   const GURL kUrl1("http://www.chromium.org/");
   const GURL kUrl2("http://www.google.com/");
 
   // Load a URL.
   contents()->NavigateAndCommit(kUrl1);
-  RenderFrameHostImpl* rfh = main_test_rfh();
-  EXPECT_EQ(RenderFrameHostImpl::STATE_DEFAULT, rfh->rfh_state());
   FrameTreeNode* node = main_test_rfh()->frame_tree_node();
+  RenderFrameHostManager* rfhm = node->render_manager();
 
   // Navigate to a different site.
   SendRequestNavigation(node, kUrl2);
@@ -169,6 +233,9 @@ TEST_F(NavigatorTestWithBrowserSideNavigation, NoContent) {
   NavigationRequest* main_request = GetNavigationRequestForFrameTreeNode(node);
   ASSERT_TRUE(main_request);
 
+  // Navigations to a different site do create a speculative RenderFrameHost.
+  EXPECT_TRUE(GetSpeculativeRenderFrameHost(rfhm));
+
   // Commit an HTTP 204 response.
   scoped_refptr<ResourceResponse> response(new ResourceResponse);
   const char kNoContentHeaders[] = "HTTP/1.1 204 No Content\0\0";
@@ -177,9 +244,11 @@ TEST_F(NavigatorTestWithBrowserSideNavigation, NoContent) {
   GetLoaderForNavigationRequest(main_request)->CallOnResponseStarted(
       response, MakeEmptyStream());
 
-  // There should be no pending RenderFrameHost; the navigation was aborted.
+  // There should be no pending nor speculative RenderFrameHost; the navigation
+  // was aborted.
   EXPECT_FALSE(GetNavigationRequestForFrameTreeNode(node));
-  EXPECT_FALSE(node->render_manager()->pending_frame_host());
+  EXPECT_FALSE(rfhm->pending_frame_host());
+  EXPECT_FALSE(GetSpeculativeRenderFrameHost(rfhm));
 
   // Now, repeat the test with 205 Reset Content.
 
@@ -188,6 +257,7 @@ TEST_F(NavigatorTestWithBrowserSideNavigation, NoContent) {
   main_test_rfh()->SendBeginNavigationWithURL(kUrl2);
   main_request = GetNavigationRequestForFrameTreeNode(node);
   ASSERT_TRUE(main_request);
+  EXPECT_TRUE(GetSpeculativeRenderFrameHost(rfhm));
 
   // Commit an HTTP 205 response.
   response = new ResourceResponse;
@@ -197,9 +267,11 @@ TEST_F(NavigatorTestWithBrowserSideNavigation, NoContent) {
   GetLoaderForNavigationRequest(main_request)->CallOnResponseStarted(
       response, MakeEmptyStream());
 
-  // There should be no pending RenderFrameHost; the navigation was aborted.
+  // There should be no pending nor speculative RenderFrameHost; the navigation
+  // was aborted.
   EXPECT_FALSE(GetNavigationRequestForFrameTreeNode(node));
-  EXPECT_FALSE(node->render_manager()->pending_frame_host());
+  EXPECT_FALSE(rfhm->pending_frame_host());
+  EXPECT_FALSE(GetSpeculativeRenderFrameHost(rfhm));
 }
 
 // PlzNavigate: Test that a new RenderFrameHost is created when doing a cross
@@ -210,41 +282,49 @@ TEST_F(NavigatorTestWithBrowserSideNavigation, CrossSiteNavigation) {
 
   contents()->NavigateAndCommit(kUrl1);
   RenderFrameHostImpl* rfh = main_test_rfh();
-  EXPECT_EQ(RenderFrameHostImpl::STATE_DEFAULT, rfh->rfh_state());
   FrameTreeNode* node = main_test_rfh()->frame_tree_node();
+  RenderFrameHostManager* rfhm = node->render_manager();
 
   // Navigate to a different site.
   SendRequestNavigation(node, kUrl2);
   main_test_rfh()->SendBeginNavigationWithURL(kUrl2);
   NavigationRequest* main_request = GetNavigationRequestForFrameTreeNode(node);
   ASSERT_TRUE(main_request);
+  EXPECT_TRUE(GetSpeculativeRenderFrameHost(rfhm));
 
   scoped_refptr<ResourceResponse> response(new ResourceResponse);
   GetLoaderForNavigationRequest(main_request)->CallOnResponseStarted(
       response, MakeEmptyStream());
-  RenderFrameHostImpl* pending_rfh =
-      node->render_manager()->pending_frame_host();
-  ASSERT_TRUE(pending_rfh);
-  EXPECT_NE(pending_rfh, rfh);
-  EXPECT_TRUE(pending_rfh->IsRenderFrameLive());
-  EXPECT_TRUE(pending_rfh->render_view_host()->IsRenderViewLive());
+  EXPECT_TRUE(GetSpeculativeRenderFrameHost(rfhm));
+
+  FrameHostMsg_DidCommitProvisionalLoad_Params params =
+      BuildSimpleDCPLParams(kUrl2);
+  main_test_rfh()->SendNavigateWithParams(&params);

[clamy, 2014/12/16 15:22:48]

Switch to using TestRenderFrameHost::SendNavigate (here and below).

[carlosk, 2014/12/19 04:27:14]

Done.

[clamy, 2014/12/19 13:35:57]

I really meant to use that precise function and not
TestWebContents::CommitPendingNavigation. Using the later will break when
https://chromiumcodereview.appspot.com/761013003/ lands (you will call
OnResponseStarted on the loader twice).

[carlosk, 2014/12/29 16:40:16]

OK. What was bugging me about that approach was that the RFH being committed was
chosen by the test without checking for which one actually had sent the commit
IPC (this was the case even with my previous change).

For this and all following cases I reverted to using
TestRenderFrameHost::SendNavigate as you suggested but also added pre-checks for
the RFH we're calling it on being the one that actually committed.

+  RenderFrameHostImpl* final_rfh = main_test_rfh();
+  ASSERT_TRUE(final_rfh);
+  EXPECT_NE(rfh, final_rfh);
+  EXPECT_TRUE(final_rfh->IsRenderFrameLive());
+  EXPECT_TRUE(final_rfh->render_view_host()->IsRenderViewLive());
+  EXPECT_FALSE(GetSpeculativeRenderFrameHost(rfhm));
 }
 
-// PlzNavigate: Test that redirects are followed.
+// PlzNavigate: Test that redirects are followed and the speculative renderer
+// logic behaves as expected.
 TEST_F(NavigatorTestWithBrowserSideNavigation, RedirectCrossSite) {
   const GURL kUrl1("http://www.chromium.org/");
   const GURL kUrl2("http://www.google.com/");
 
   contents()->NavigateAndCommit(kUrl1);
   RenderFrameHostImpl* rfh = main_test_rfh();
-  EXPECT_EQ(RenderFrameHostImpl::STATE_DEFAULT, rfh->rfh_state());
   FrameTreeNode* node = main_test_rfh()->frame_tree_node();
+  RenderFrameHostManager* rfhm = node->render_manager();
 
   // Navigate to a URL on the same site.
   SendRequestNavigation(node, kUrl1);
   main_test_rfh()->SendBeginNavigationWithURL(kUrl1);
   NavigationRequest* main_request = GetNavigationRequestForFrameTreeNode(node);
   ASSERT_TRUE(main_request);
+  EXPECT_FALSE(GetSpeculativeRenderFrameHost(rfhm));
 
   // It then redirects to another site.
   net::RedirectInfo redirect_info;
@@ -252,38 +332,48 @@ TEST_F(NavigatorTestWithBrowserSideNavigation, RedirectCrossSite) {
   redirect_info.new_method = "GET";
   redirect_info.new_url = kUrl2;
   redirect_info.new_first_party_for_cookies = kUrl2;
- scoped_refptr<ResourceResponse> response(new ResourceResponse);
+  scoped_refptr<ResourceResponse> response(new ResourceResponse);
   GetLoaderForNavigationRequest(main_request)->CallOnRequestRedirected(
       redirect_info, response);
 
   // The redirect should have been followed.
   EXPECT_EQ(1, GetLoaderForNavigationRequest(main_request)->redirect_count());
+  EXPECT_FALSE(GetSpeculativeRenderFrameHost(rfhm));
 
   // Then it commits.
   response = new ResourceResponse;
   GetLoaderForNavigationRequest(main_request)->CallOnResponseStarted(
       response, MakeEmptyStream());
-  RenderFrameHostImpl* pending_rfh =
-      node->render_manager()->pending_frame_host();
-  ASSERT_TRUE(pending_rfh);
-  EXPECT_NE(pending_rfh, rfh);
-  EXPECT_TRUE(pending_rfh->IsRenderFrameLive());
-  EXPECT_TRUE(pending_rfh->render_view_host()->IsRenderViewLive());
+  RenderFrameHost* final_srfh = GetSpeculativeRenderFrameHost(rfhm);
+  EXPECT_TRUE(final_srfh);
+
+  // And commits provisional load.
+  FrameHostMsg_DidCommitProvisionalLoad_Params params =
+      BuildSimpleDCPLParams(kUrl2);
+  main_test_rfh()->SendNavigateWithParams(&params);
+  RenderFrameHostImpl* final_rfh = main_test_rfh();
+  ASSERT_TRUE(final_rfh);
+  EXPECT_NE(rfh, final_rfh);
+  EXPECT_EQ(final_srfh, final_rfh);

[clamy, 2014/12/16 15:22:48]

nit: could you rename one of those parameters? final_srfh and final_rfh are a
bit hard to tell apart.

[carlosk, 2014/12/19 04:27:14]

Done.

+  EXPECT_TRUE(final_rfh->IsRenderFrameLive());
+  EXPECT_TRUE(final_rfh->render_view_host()->IsRenderViewLive());
+  EXPECT_FALSE(GetSpeculativeRenderFrameHost(rfhm));
 }
 
-// PlzNavigate: Test that a navigation is cancelled if another request has been
-// issued in the meantime.
+// PlzNavigate: Test that a navigation is canceled if another request has been
+// issued in the meantime. Also confirms that the speculative renderer is
+// correctly updated in the process.
 TEST_F(NavigatorTestWithBrowserSideNavigation, ReplacePendingNavigation) {
   const GURL kUrl0("http://www.wikipedia.org/");
-  const GURL kUrl0_site = SiteInstance::GetSiteForURL(browser_context(), kUrl0);
   const GURL kUrl1("http://www.chromium.org/");
+  const GURL kUrl1_site = SiteInstance::GetSiteForURL(browser_context(), kUrl1);
   const GURL kUrl2("http://www.google.com/");
   const GURL kUrl2_site = SiteInstance::GetSiteForURL(browser_context(), kUrl2);
 
   // Initialization.
   contents()->NavigateAndCommit(kUrl0);
   FrameTreeNode* node = main_test_rfh()->frame_tree_node();
-  EXPECT_EQ(kUrl0_site, main_test_rfh()->GetSiteInstance()->GetSiteURL());
+  RenderFrameHostManager* rfhm = node->render_manager();
 
   // Request navigation to the 1st URL.
   SendRequestNavigation(node, kUrl1);
@@ -294,6 +384,14 @@ TEST_F(NavigatorTestWithBrowserSideNavigation, ReplacePendingNavigation) {
   base::WeakPtr<TestNavigationURLLoader> loader1 =
       GetLoaderForNavigationRequest(request1)->AsWeakPtr();
 
+  // Confirm a speculative RFH was created.
+  ASSERT_TRUE(GetSpeculativeRenderFrameHost(rfhm));
+  int32 site_instance_id_1 =
+      GetSpeculativeRenderFrameHost(rfhm)->GetSiteInstance()->GetId();
+  EXPECT_EQ(
+      kUrl1_site,
+      GetSpeculativeRenderFrameHost(rfhm)->GetSiteInstance()->GetSiteURL());
+
   // Request navigation to the 2nd URL; the NavigationRequest must have been
   // replaced by a new one with a different URL.
   SendRequestNavigation(node, kUrl2);
@@ -305,23 +403,39 @@ TEST_F(NavigatorTestWithBrowserSideNavigation, ReplacePendingNavigation) {
   // Confirm that the first loader got destroyed.
   EXPECT_FALSE(loader1);
 
-  // Confirm that the commit corresponds to the new request.
+  // Confirm that a new speculative RFH was created.
+  ASSERT_TRUE(GetSpeculativeRenderFrameHost(rfhm));
+  int32 site_instance_id_2 =
+      GetSpeculativeRenderFrameHost(rfhm)->GetSiteInstance()->GetId();
+  EXPECT_NE(site_instance_id_1, site_instance_id_2);
+
+  // Commit.
   scoped_refptr<ResourceResponse> response(new ResourceResponse);
   GetLoaderForNavigationRequest(request2)->CallOnResponseStarted(
       response, MakeEmptyStream());
-  RenderFrameHostImpl* pending_rfh =
-      node->render_manager()->pending_frame_host();
-  ASSERT_TRUE(pending_rfh);
-  EXPECT_EQ(kUrl2_site, pending_rfh->GetSiteInstance()->GetSiteURL());
+
+  // And commit provisional load.
+  FrameHostMsg_DidCommitProvisionalLoad_Params params =
+      BuildSimpleDCPLParams(kUrl2);
+  main_test_rfh()->SendNavigateWithParams(&params);
+
+  // Confirm that the commit corresponds to the new request.
+  ASSERT_TRUE(main_test_rfh());
+  EXPECT_EQ(kUrl2_site, main_test_rfh()->GetSiteInstance()->GetSiteURL());
+
+  // Confirm that the committed RFH is the new speculative one.
+  EXPECT_EQ(site_instance_id_2, main_test_rfh()->GetSiteInstance()->GetId());
 }
 
 // PlzNavigate: Test that a reload navigation is properly signaled to the
-// renderer when the navigation can commit.
+// renderer when the navigation can commit. Speculative renderers should not be
+// created at any step.
 TEST_F(NavigatorTestWithBrowserSideNavigation, Reload) {
   const GURL kUrl("http://www.google.com/");
   contents()->NavigateAndCommit(kUrl);
 
   FrameTreeNode* node = main_test_rfh()->frame_tree_node();
+  RenderFrameHostManager* rfhm = node->render_manager();
   SendRequestNavigationWithParameters(
       node, kUrl, Referrer(), ui::PAGE_TRANSITION_LINK,
       NavigationController::RELOAD);
@@ -332,9 +446,12 @@ TEST_F(NavigatorTestWithBrowserSideNavigation, Reload) {
   ASSERT_TRUE(main_request != NULL);
   EXPECT_EQ(FrameMsg_Navigate_Type::RELOAD,
             main_request->common_params().navigation_type);
+  EXPECT_FALSE(GetSpeculativeRenderFrameHost(rfhm));
+
   int page_id = contents()->GetMaxPageIDForSiteInstance(
                     main_test_rfh()->GetSiteInstance()) + 1;
   main_test_rfh()->SendNavigate(page_id, kUrl);
+  EXPECT_FALSE(GetSpeculativeRenderFrameHost(rfhm));
 
   // Now do a shift+reload.
   SendRequestNavigationWithParameters(
@@ -346,6 +463,151 @@ TEST_F(NavigatorTestWithBrowserSideNavigation, Reload) {
   ASSERT_TRUE(main_request != NULL);
   EXPECT_EQ(FrameMsg_Navigate_Type::RELOAD_IGNORING_CACHE,
             main_request->common_params().navigation_type);
+  EXPECT_FALSE(GetSpeculativeRenderFrameHost(rfhm));
+}
+
+// PlzNavigate: Confirm that a speculative RenderFrameHost is used when
+// navigating from one site to the another.
+TEST_F(NavigatorTestWithBrowserSideNavigation,
+       SpeculativeRendererWorksBaseCase) {
+  // Navigate to an initial site.
+  const GURL kUrlInit("http://wikipedia.org/");
+  contents()->NavigateAndCommit(kUrlInit);
+  FrameTreeNode* node = main_test_rfh()->frame_tree_node();
+  RenderFrameHostManager* rfhm = node->render_manager();
+
+  // Begin navigating to another site.
+  const GURL kUrl("http://google.com/");
+  SendRequestNavigation(node, kUrl);
+  contents()->GetMainFrame()->SendBeginNavigationWithURL(kUrl);
+  ASSERT_TRUE(GetSpeculativeRenderFrameHost(rfhm));
+  EXPECT_NE(GetSpeculativeRenderFrameHost(rfhm), main_test_rfh());
+  EXPECT_EQ(
+      SiteInstanceImpl::GetSiteForURL(browser_context(), kUrl),
+      GetSpeculativeRenderFrameHost(rfhm)->GetSiteInstance()->GetSiteURL());
+  EXPECT_FALSE(rfhm->pending_frame_host());
+  int32 site_instance_id =
+      GetSpeculativeRenderFrameHost(rfhm)->GetSiteInstance()->GetId();
+
+  // Ask Navigator to commit the navigation by simulating a call to
+  // OnResponseStarted.
+  scoped_refptr<ResourceResponse> response(new ResourceResponse);
+  GetLoaderForNavigationRequest(GetNavigationRequestForFrameTreeNode(node))
+      ->CallOnResponseStarted(response, MakeEmptyStream());
+  ASSERT_TRUE(GetSpeculativeRenderFrameHost(rfhm));
+  EXPECT_EQ(site_instance_id,
+            GetSpeculativeRenderFrameHost(rfhm)->GetSiteInstance()->GetId());
+  EXPECT_FALSE(rfhm->pending_frame_host());
+
+  // Invoke OnDidCommitProvisionalLoad.
+  FrameHostMsg_DidCommitProvisionalLoad_Params params =
+      BuildSimpleDCPLParams(kUrl);
+  main_test_rfh()->SendNavigateWithParams(&params);
+  EXPECT_EQ(site_instance_id, main_test_rfh()->GetSiteInstance()->GetId());
+  EXPECT_FALSE(GetSpeculativeRenderFrameHost(rfhm));
+  EXPECT_FALSE(rfhm->pending_frame_host());
+}
+
+// PlzNavigate: Confirm that a speculative RenderFrameHost is thrown away when
+// the final URL's site differs from the initial one due to redirects.
+TEST_F(NavigatorTestWithBrowserSideNavigation,
+       SpeculativeRendererDiscardedAfterRedirectToAnotherSite) {
+  // Navigate to an initial site.
+  const GURL kUrlInit("http://wikipedia.org/");
+  contents()->NavigateAndCommit(kUrlInit);
+  FrameTreeNode* node = main_test_rfh()->frame_tree_node();
+  RenderFrameHostManager* rfhm = node->render_manager();
+  int32 init_site_instance_id = main_test_rfh()->GetSiteInstance()->GetId();
+
+  // Begin navigating to another site.
+  const GURL kUrl("http://google.com/");
+  SendRequestNavigation(node, kUrl);
+  contents()->GetMainFrame()->SendBeginNavigationWithURL(kUrl);
+  int32 site_instance_id =
+      GetSpeculativeRenderFrameHost(rfhm)->GetSiteInstance()->GetId();
+  EXPECT_EQ(init_site_instance_id, main_test_rfh()->GetSiteInstance()->GetId());
+  ASSERT_TRUE(GetSpeculativeRenderFrameHost(rfhm));
+  EXPECT_NE(GetSpeculativeRenderFrameHost(rfhm), main_test_rfh());
+  EXPECT_EQ(
+      SiteInstanceImpl::GetSiteForURL(browser_context(), kUrl),
+      GetSpeculativeRenderFrameHost(rfhm)->GetSiteInstance()->GetSiteURL());
+
+  // It then redirects to yet another site.
+  NavigationRequest* main_request = GetNavigationRequestForFrameTreeNode(node);
+  ASSERT_TRUE(main_request);
+  const GURL kUrlRedirect("https://www.google.com/");
+  net::RedirectInfo redirect_info;
+  redirect_info.status_code = 302;
+  redirect_info.new_method = "GET";
+  redirect_info.new_url = kUrlRedirect;
+  redirect_info.new_first_party_for_cookies = kUrlRedirect;
+  scoped_refptr<ResourceResponse> response(new ResourceResponse);
+  GetLoaderForNavigationRequest(main_request)
+      ->CallOnRequestRedirected(redirect_info, response);
+  EXPECT_EQ(init_site_instance_id, main_test_rfh()->GetSiteInstance()->GetId());
+  ASSERT_TRUE(GetSpeculativeRenderFrameHost(rfhm));
+
+  // TODO(carlosk): once the speculative RenderFrameHost updates with redirects
+  // this next check will be changed to verify that it actually happens.
+  EXPECT_EQ(site_instance_id,
+            GetSpeculativeRenderFrameHost(rfhm)->GetSiteInstance()->GetId());
+
+  // Commit the navigation with Navigator by simulating the call to
+  // OnResponseStarted.
+  response = new ResourceResponse;
+  GetLoaderForNavigationRequest(main_request)
+      ->CallOnResponseStarted(response, MakeEmptyStream());
+  EXPECT_EQ(init_site_instance_id, main_test_rfh()->GetSiteInstance()->GetId());
+
+  // Once commit happens the speculative RenderFrameHost is already updated to
+  // match the known final SiteInstance.
+  ASSERT_TRUE(GetSpeculativeRenderFrameHost(rfhm));
+  EXPECT_EQ(
+      SiteInstanceImpl::GetSiteForURL(browser_context(), kUrlRedirect),
+      GetSpeculativeRenderFrameHost(rfhm)->GetSiteInstance()->GetSiteURL());
+  int32 redirect_site_instance_id =
+      GetSpeculativeRenderFrameHost(rfhm)->GetSiteInstance()->GetId();
+
+  // Invoke OnDidCommitProvisionalLoad.
+  FrameHostMsg_DidCommitProvisionalLoad_Params params =
+      BuildSimpleDCPLParams(kUrl);
+  main_test_rfh()->SendNavigateWithParams(&params);
+
+  // And finally on commit-provisional-load the already created RenderFrameHost
+  // is made active.
+  EXPECT_EQ(redirect_site_instance_id,
+            main_test_rfh()->GetSiteInstance()->GetId());
+  EXPECT_FALSE(GetSpeculativeRenderFrameHost(rfhm));
+}
+
+// PlzNavigate: Verify that a previously swapped-out RenderFrameHost is
+// correctly reused when spawning a speculative RenderFrameHost in a navigation
+// using the same SiteInstance.
+TEST_F(NavigatorTestWithBrowserSideNavigation,
+       SpeculativeRendererReuseSwappedOutRFH) {
+  // Navigate to an initial site.
+  const GURL kUrl1("http://wikipedia.org/");
+  contents()->NavigateAndCommit(kUrl1);
+  RenderFrameHostImpl* rfh1 = main_test_rfh();
+  RenderFrameHostManager* rfhm = rfh1->frame_tree_node()->render_manager();
+
+  // Increment active frame count to cause the RenderFrameHost to be swapped out
+  // (instead of immediately destroyed).
+  rfh1->GetSiteInstance()->increment_active_frame_count();
+
+  // Then to another to swap-out the initial RenderFrameHost.

[clamy, 2014/12/16 15:22:48]

s/Then to another/Navigate to another site

[carlosk, 2014/12/19 04:27:14]

Done.

+  const GURL kUrl2("http://chromium.org/");
+  contents()->NavigateAndCommit(kUrl2);
+  ASSERT_NE(rfh1, main_test_rfh());
+  EXPECT_NE(RenderFrameHostImpl::STATE_DEFAULT, rfh1->rfh_state());
+  EXPECT_EQ(RenderFrameHostImpl::STATE_DEFAULT, main_test_rfh()->rfh_state());
+  EXPECT_TRUE(rfhm->IsOnSwappedOutList(rfh1));
+
+  // Now goes back to the initial site.

[clamy, 2014/12/16 15:22:48]

s/goes/go

I would add a comment along the lines of: The swapped-out initial
RenderFrameHost should be reused.

[carlosk, 2014/12/19 04:27:14]

Done.

+  contents()->NavigateAndCommit(kUrl1);

[clamy, 2014/12/16 15:22:48]

I think you could actually split the NavigateAndCommit here to check that you
actually have a speculative rfh, and that it is the swapped out initial RFH.

[carlosk, 2014/12/19 04:27:14]

Done.

+  EXPECT_EQ(rfh1, main_test_rfh());
+  EXPECT_EQ(RenderFrameHostImpl::STATE_DEFAULT, rfh1->rfh_state());
+  EXPECT_FALSE(rfhm->IsOnSwappedOutList(rfh1));
 }
 
 }  // namespace content