Navigation transitions: Block first response until after transitions have run.

content/browser/web_contents/web_contents_impl.h

Index: content/browser/web_contents/web_contents_impl.h
diff --git a/content/browser/web_contents/web_contents_impl.h b/content/browser/web_contents/web_contents_impl.h
index 8278efbefb179207529d871450e75c25602ab472..b35024a9d5909c20f2c1feedabfc8efd8730231d 100644
--- a/content/browser/web_contents/web_contents_impl.h
+++ b/content/browser/web_contents/web_contents_impl.h
@@ -328,6 +328,8 @@ class CONTENT_EXPORT WebContentsImpl
   virtual void DidStartLoading(RenderFrameHost* render_frame_host,
                                bool to_different_document) OVERRIDE;
   virtual void SwappedOut(RenderFrameHost* render_frame_host) OVERRIDE;
+  virtual void DidDeferAfterResponseStarted() OVERRIDE;
+  virtual bool WillHandleDeferAfterResponseStarted() OVERRIDE;
   virtual void WorkerCrashed(RenderFrameHost* render_frame_host) OVERRIDE;
   virtual void ShowContextMenu(RenderFrameHost* render_frame_host,
                                const ContextMenuParams& params) OVERRIDE;
@@ -625,6 +627,22 @@ class CONTENT_EXPORT WebContentsImpl
   // currently focused frame.
   void SelectRange(const gfx::Point& start, const gfx::Point& end);
 
+  // Notifies the TransitionRequestManager that the main frame navigation is
+  // a transition navigation.
+  void SetHasPendingTransitionRequest(bool has_pending_transition);
+
+  // Notifies the main frame that it can continue navigation (if it was deferred
+  // immediately at first response).
+  void ResumeResponseDeferredAtStart();
+
+  typedef base::Callback<void()> DidDeferCallback;
+
+  // Callback to be used when the WebContentsImpl handles a navigation
+  // transition.
+  void set_did_defer_callback_for_testing(const DidDeferCallback& callback) {
+    did_defer_callback_for_testing_ = callback;

[shatch, 2014/06/14 00:41:37]

Wanted a way to get a callback for the browsertests so that we could see that
DidDeferAfterResponseStarted was being called correctly, and resume the
navigation. Is there a better way to do this?

+  }
+
  private:
   friend class TestNavigationObserver;
   friend class WebContentsAddedObserver;
@@ -1128,6 +1146,8 @@ class CONTENT_EXPORT WebContentsImpl
   // Whether the last JavaScript dialog shown was suppressed. Used for testing.
   bool last_dialog_suppressed_;
 
+  DidDeferCallback did_defer_callback_for_testing_;
+
   scoped_ptr<GeolocationDispatcherHost> geolocation_dispatcher_host_;
 
   DISALLOW_COPY_AND_ASSIGN(WebContentsImpl);