PlzNavigate: Create the speculative renderer earlier.

content/browser/frame_host/navigator_impl.cc

Index: content/browser/frame_host/navigator_impl.cc
diff --git a/content/browser/frame_host/navigator_impl.cc b/content/browser/frame_host/navigator_impl.cc
index aff92459639e88b0a6b77752b4de2b3ae1ea43d8..7ee98057cf107da0bd196581ca2b4cf848e93255 100644
--- a/content/browser/frame_host/navigator_impl.cc
+++ b/content/browser/frame_host/navigator_impl.cc
@@ -600,8 +600,9 @@ void NavigatorImpl::OnBeforeUnloadACK(FrameTreeNode* frame_tree_node,
   DCHECK_EQ(NavigationRequest::WAITING_FOR_RENDERER_RESPONSE,
             navigation_request->state());
 
+  // If the navigation is allowed to proceed, send the request to the IO thread.
   if (proceed)
-    BeginNavigation(frame_tree_node);
+    navigation_request->BeginNavigation();
   else
     CancelNavigation(frame_tree_node);
 }
@@ -655,7 +656,7 @@ void NavigatorImpl::OnBeginNavigation(
     navigation_data_.reset();
   }
 
-  BeginNavigation(frame_tree_node);
+  frame_tree_node->navigation_request()->BeginNavigation();
 }
 
 // PlzNavigate
@@ -803,42 +804,31 @@ void NavigatorImpl::RequestNavigation(
   CHECK(base::CommandLine::ForCurrentProcess()->HasSwitch(
       switches::kEnableBrowserSideNavigation));
   DCHECK(frame_tree_node);
+
+  // This value must be set here because SetNavigationRequest might change the
+  // renderer live/non-live status and change this result.
+  bool should_dispatch_beforeunload =
+      frame_tree_node->current_frame_host()->ShouldDispatchBeforeUnload();
   FrameMsg_Navigate_Type::Value navigation_type =
       GetNavigationType(controller_->GetBrowserContext(), entry, reload_type);
-  scoped_ptr<NavigationRequest> navigation_request =
+  frame_tree_node->SetNavigationRequest(
       NavigationRequest::CreateBrowserInitiated(frame_tree_node, entry,
                                                 navigation_type,
-                                                navigation_start, controller_);
-  frame_tree_node->SetNavigationRequest(navigation_request.Pass());
-  frame_tree_node->navigation_request()->SetWaitingForRendererResponse();
+                                                navigation_start, controller_));
+  NavigationRequest* navigation_request = frame_tree_node->navigation_request();
 
   // Have the current renderer execute its beforeUnload event if needed. If it
-  // is not needed (eg. the renderer is not live), BeginNavigation should get
-  // called. If the navigation is synchronous and same-site, then it can be sent
-  // directly to the renderer (currently this is the case for navigations that
-  // do not make network requests such as data urls or Javascript urls).
-  if (NavigationRequest::ShouldMakeNetworkRequest(
-          frame_tree_node->navigation_request()->common_params().url)) {
+  // is not needed NavigationRequest::BeginNavigation should get called. This is
+  // the case if the renderer is not live, this is a subframe navigation, or if

[nasko, 2015/06/12 17:22:22]

The details of when running the beforeUnload handler is required or not
shouldn't be documented here, but rather at ShouldDispatchBeforeUnload.

[carlosk, 2015/06/15 19:11:54]

I'm assuming the same logic applies to the details concerning
ShouldMakeNetworkRequest.

So I updated this comment to not go into either of them and moved information
out to the declaration of ShouldMakeNetworkRequest (ShouldDispatchBeforeUnload
already had the concerned details).

+  // the navigation is synchronous and same-site (such as for data URLs or
+  // Javascript URLs, when no network request is made).
+  if (should_dispatch_beforeunload &&
+      NavigationRequest::ShouldMakeNetworkRequest(
+          navigation_request->common_params().url)) {
+    navigation_request->SetWaitingForRendererResponse();
     frame_tree_node->current_frame_host()->DispatchBeforeUnload(true);
   } else {
-    BeginNavigation(frame_tree_node);
-  }
-}
-
-void NavigatorImpl::BeginNavigation(FrameTreeNode* frame_tree_node) {
-  NavigationRequest* navigation_request = frame_tree_node->navigation_request();
-
-  // A browser-initiated navigation could have been cancelled while it was
-  // waiting for the BeforeUnload event to execute.
-  if (!navigation_request)
-    return;
-
-  // Start the request.
-   if (navigation_request->BeginNavigation()) {
-    // If the request was sent to the IO thread, notify the
-    // RenderFrameHostManager so it can speculatively create a RenderFrameHost
-    // (and potentially a new renderer process) in parallel.
-    frame_tree_node->render_manager()->BeginNavigation(*navigation_request);
+    navigation_request->BeginNavigation();
   }
 }