Reland #2 Remove the is_loading_ field from WebContentsImpl

content/browser/frame_host/render_frame_host_manager.cc

Index: content/browser/frame_host/render_frame_host_manager.cc
diff --git a/content/browser/frame_host/render_frame_host_manager.cc b/content/browser/frame_host/render_frame_host_manager.cc
index 03212114c51a63ca4597387490b5dba014a6e5fe..268da04164d92ddf264d3e3f9a30ba277e2a7e2a 100644
--- a/content/browser/frame_host/render_frame_host_manager.cc
+++ b/content/browser/frame_host/render_frame_host_manager.cc
@@ -437,6 +437,7 @@ void RenderFrameHostManager::OnCrossSiteResponse(
   // should probably cancel the request in that case.
   DCHECK(pending_render_frame_host == pending_render_frame_host_.get() ||
          pending_render_frame_host == render_frame_host_.get());
+  DCHECK(frame_tree_node_->IsLoading());

[Charlie Reis, 2016/02/19 05:24:54]

Is there a race where this could fail, where the UI thread sets IsLoading to
false just before the IO thread posts the task to OnCrossSiteResponse?  (Not
sure, just checking.)

[clamy, 2016/02/19 12:02:05]

That would mean that we set is_loading to false not in response to an IPC (they
go through the IO thread) or an IO event. The only possible case I see is when
the user closes the BeforeUnload dialog and we reset the load state. I modified
the code so that it is now a boolean that we use to fire or not the
DidStopLoading at the end of the function.

 
   // Store the transferring request so that we can release it if the transfer
   // navigation matches.
@@ -448,6 +449,11 @@ void RenderFrameHostManager::OnCrossSiteResponse(
       pending_render_frame_host->PassNavigationHandleOwnership();
   DCHECK(transfer_navigation_handle_);
 
+  // Set the transferring RenderFrameHost as not loading, so that it does not
+  // emit a DidStopLoading notification if it is destroyed when creating the
+  // new navigating RenderFrameHost.
+  pending_render_frame_host->set_is_loading(false);
+
   // Sanity check that the params are for the correct frame and process.
   // These should match the RenderFrameHost that made the request.
   // If it started as a cross-process navigation via OpenURL, this is the
@@ -480,6 +486,11 @@ void RenderFrameHostManager::OnCrossSiteResponse(
   // If the navigation continued, the NavigationHandle should have been
   // transfered to a RenderFrameHost. In the other cases, it should be cleared.
   transfer_navigation_handle_.reset();
+
+  // If the navigation in the new renderer did not start, inform the
+  // FrameTreeNode that it stopped loading.
+  if (!frame_tree_node_->IsLoading())
+    frame_tree_node_->DidStopLoading();
 }
 
 void RenderFrameHostManager::DidNavigateFrame(
@@ -912,8 +923,12 @@ RenderFrameHostImpl* RenderFrameHostManager::GetFrameHostForNavigation(
 void RenderFrameHostManager::CleanUpNavigation() {
   CHECK(IsBrowserSideNavigationEnabled());
   render_frame_host_->ClearPendingWebUI();
-  if (speculative_render_frame_host_)
+  if (speculative_render_frame_host_) {
+    bool was_loading = speculative_render_frame_host_->is_loading();
     DiscardUnusedFrame(UnsetSpeculativeRenderFrameHost());
+    if (was_loading)
+      frame_tree_node_->DidStopLoading();
+  }
 }
 
 // PlzNavigate
@@ -2002,6 +2017,7 @@ void RenderFrameHostManager::CommitPending() {
     // now to make sure the sad tab shows up, etc.
     DCHECK(!render_frame_host_->IsRenderFrameLive());
     DCHECK(!render_frame_host_->render_view_host()->IsRenderViewLive());
+    render_frame_host_->ResetLoadingState();
     delegate_->RenderProcessGoneFromRenderManager(
         render_frame_host_->render_view_host());
   }
@@ -2253,7 +2269,11 @@ void RenderFrameHostManager::CancelPending() {
   TRACE_EVENT1("navigation", "RenderFrameHostManager::CancelPending",
                "FrameTreeNode id", frame_tree_node_->frame_tree_node_id());
   render_frame_host_->ClearPendingWebUI();
+
+  bool pending_was_loading = pending_render_frame_host_->is_loading();
   DiscardUnusedFrame(UnsetPendingRenderFrameHost());
+  if (pending_was_loading)
+    frame_tree_node_->DidStopLoading();
 }
 
 scoped_ptr<RenderFrameHostImpl>