PlzNavigate: add cancel navigation logic for uncommitted requests

content/browser/frame_host/navigation_request.cc

Index: content/browser/frame_host/navigation_request.cc
diff --git a/content/browser/frame_host/navigation_request.cc b/content/browser/frame_host/navigation_request.cc
index fb46ae59b3d9c10ad87d021dd60dd5010efb342f..c968d5732b7c400e4f0646cf119854dc8155b9c2 100644
--- a/content/browser/frame_host/navigation_request.cc
+++ b/content/browser/frame_host/navigation_request.cc
@@ -21,17 +21,33 @@ void OnBeginNavigation(const NavigationRequestInfo& info,
       info, request_body, frame_node_id);
 }
 
+void OnDestructNavigationRequest(int64 navigation_request_id,
+                                 int64 frame_node_id) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+  ResourceDispatcherHostImpl::Get()->CancelNavigationRequest(
+      navigation_request_id, frame_node_id);
+}
+
 }  // namespace
 
+int64 NavigationRequest::next_navigation_request_id_ = 1;

[clamy, 2014/08/14 13:19:06]

This should be changed to 0 as we use pre-increment (see comment below).

[carlosk, 2014/08/14 17:07:10]

Done.

+
 NavigationRequest::NavigationRequest(const NavigationRequestInfo& info,
                                      int64 frame_node_id)
-  : info_(info),
+  : navigation_request_id_(next_navigation_request_id_++),

[clamy, 2014/08/14 13:19:06]

The styleguide mandates using ++next_navigation_request_id_ (see
http://google-styleguide.googlecode.com/svn/trunk/cppguide.xml#Preincrement_a...)

[carlosk, 2014/08/14 17:07:10]

Done.

+    info_(info),
     frame_node_id_(frame_node_id) {
 }
 
 NavigationRequest::~NavigationRequest() {
-  // TODO(clamy): Cancel the corresponding request in ResourceDispatcherHost if
-  // it has not commited yet.
+  // TODO(carlosk): Figure out when the navigation actually needs to be
+  // cancelled.
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  BrowserThread::PostTask(
+      BrowserThread::IO,
+      FROM_HERE,
+      base::Bind(&OnDestructNavigationRequest,
+                 navigation_request_id_, frame_node_id_));
 }
 
 void NavigationRequest::BeginNavigation(