Make Page Visibility API work when the browser window is visible or not

content/public/browser/render_widget_host_view.h

 // Copyright (c) 2012 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 CONTENT_PUBLIC_BROWSER_RENDER_WIDGET_HOST_VIEW_H_
 #define CONTENT_PUBLIC_BROWSER_RENDER_WIDGET_HOST_VIEW_H_
 
 #include "base/basictypes.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/strings/string16.h"
@@ skipping 71 matching lines @@
   virtual void Focus() = 0;
   // Returns true if the View currently has the focus.
   virtual bool HasFocus() const = 0;
   // Returns true is the current display surface is available.
   virtual bool IsSurfaceAvailableForCopy() const = 0;
 
   // Shows/hides the view.  These must always be called together in pairs.
   // It is not legal to call Hide() multiple times in a row.
   virtual void Show() = 0;
   virtual void Hide() = 0;
-
+  virtual void Hide(bool content_visible) = 0;
   // Whether the view is showing.
   virtual bool IsShowing() = 0;
 
   // Indicates if the view is currently occluded (e.g, not visible because it's
   // covered up by other windows), and as a result the view's renderer may be
   // suspended. If Show() is called on a view then its state should be re-set to
   // being un-occluded (an explicit WasUnOccluded call will not be made for
   // that). These calls are not necessarily made in pairs.
   virtual void WasUnOccluded() = 0;
   virtual void WasOccluded() = 0;
@@ skipping 68 matching lines @@
   // Returns |true| if text is currently being spoken by Mac OS X.
   virtual bool IsSpeaking() const = 0;
   // Stops speaking, if it is currently in progress.
   virtual void StopSpeaking() = 0;
 #endif  // defined(OS_MACOSX)
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_RENDER_WIDGET_HOST_VIEW_H_