Free temporary GPU and memory resources held by inactive or hidden 2D canvases

Source/core/frame/Frame.cpp

 /*
  * Copyright (C) 1998, 1999 Torben Weis <weis@kde.org>
  *                     1999 Lars Knoll <knoll@kde.org>
  *                     1999 Antti Koivisto <koivisto@kde.org>
  *                     2000 Simon Hausmann <hausmann@kde.org>
  *                     2000 Stefan Schimanski <1Stein@gmx.de>
  *                     2001 George Staikos <staikos@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2005 Alexey Proskuryakov <ap@nypop.com>
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
@@ skipping 320 matching lines @@
         return 0;
     // FIXME: If <object> is ever fixed to disassociate itself from frames
     // that it has started but canceled, then this can turn into an ASSERT
     // since ownerElement() would be 0 when the load is canceled.
     // https://bugs.webkit.org/show_bug.cgi?id=18585
     if (!object->isRenderPart())
         return 0;
     return toRenderPart(object);
 }
 
-void Frame::dispatchVisibilityStateChangeEvent()
+void Frame::didChangeVisibilityState()
 {
     if (document())
-        document()->dispatchVisibilityStateChangeEvent();
+        document()->didChangeVisibilityState();
 
     Vector<RefPtr<Frame> > childFrames;
     for (Frame* child = tree().firstChild(); child; child = child->tree().nextSibling())
         childFrames.append(child);
 
     for (size_t i = 0; i < childFrames.size(); ++i)
-        childFrames[i]->dispatchVisibilityStateChangeEvent();
+        childFrames[i]->didChangeVisibilityState();
 }
 
 void Frame::willDetachFrameHost()
 {
     // We should never be detatching the page during a Layout.
     RELEASE_ASSERT(!m_view || !m_view->isInPerformLayout());
 
     if (Frame* parent = tree().parent())
         parent->loader().checkLoadComplete();
 
@@ skipping 377 matching lines @@
     if (!m_host)
         return 0;
 
     double ratio = m_host->deviceScaleFactor();
     if (RuntimeEnabledFeatures::devicePixelRatioIncludesZoomEnabled())
         ratio *= pageZoomFactor();
     return ratio;
 }
 
 } // namespace WebCore