PlzNavigate: fix timing issue in app window creation

extensions/browser/app_window/app_window.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef EXTENSIONS_BROWSER_APP_WINDOW_APP_WINDOW_H_
 #define EXTENSIONS_BROWSER_APP_WINDOW_APP_WINDOW_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 224 matching lines @@
   NativeAppWindow* GetBaseWindow();
   gfx::NativeWindow GetNativeWindow();
 
   // Returns the bounds that should be reported to the renderer.
   gfx::Rect GetClientBounds() const;
 
   // NativeAppWindows should call this to determine what the window's title
   // is on startup and from within UpdateWindowTitle().
   base::string16 GetTitle() const;
 
+  // |callback| will then be called when the first navigation in the window is
+  // ready to commit.
+  void SetOnFirstCommitCallback(const base::Closure& callback);
+
+  // Called when the first navigation in the window is ready to commit.
+  void OnReadyToCommitFirstNavigation();
+
   // Call to notify ShellRegistry and delete the window. Subclasses should
   // invoke this method instead of using "delete this".
   void OnNativeClose();
 
   // Should be called by native implementations when the window size, position,
   // or minimized/maximized state has changed.
   void OnNativeWindowChanged();
 
   // Should be called by native implementations when the window is activated.
   void OnNativeWindowActivated();
@@ skipping 293 matching lines @@
   // reinstated when the window exits fullscreen and moves away from the
   // taskbar.
   bool cached_always_on_top_;
 
   // Whether |alpha_enabled| was set in the CreateParams.
   bool requested_alpha_enabled_;
 
   // Whether |is_ime_window| was set in the CreateParams.
   bool is_ime_window_;
 
+  // PlzNavigate: this is called when the first navigation is ready to commit.
+  base::Closure on_first_commit_callback_;
+
   base::WeakPtrFactory<AppWindow> image_loader_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(AppWindow);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_BROWSER_APP_WINDOW_APP_WINDOW_H_