Downgrade some lifecycle update calls to not include paint if not necessary.

third_party/WebKit/Source/web/WebViewImpl.cpp

 /*
  * Copyright (C) 2011, 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 3416 matching lines @@
     if (!page()->mainFrame()->isLocalFrame())
         return IntSize();
     LayoutViewItem root = page()->deprecatedLocalMainFrame()->contentLayoutItem();
     if (root.isNull())
         return IntSize();
     return root.documentRect().size();
 }
 
 WebSize WebViewImpl::contentsPreferredMinimumSize()
 {
-    updateAllLifecyclePhases();
+    if (mainFrameImpl())
+        mainFrameImpl()->frame()->view()->updateLifecycleToCompositingCleanPlusScrolling();
 
     Document* document = m_page->mainFrame()->isLocalFrame() ? m_page->deprecatedLocalMainFrame()->document() : nullptr;
     if (!document || !document->layoutView() || !document->documentElement() || !document->documentElement()->layoutBox())
         return WebSize();
 
     int widthScaled = document->layoutView()->minPreferredLogicalWidth().round(); // Already accounts for zoom.
     int heightScaled = document->documentElement()->layoutBox()->scrollHeight().round();
     return IntSize(widthScaled, heightScaled);
 }
 
@@ skipping 1146 matching lines @@
 {
     // TODO(oshima): Investigate if this should return the ScreenInfo's scale factor rather than
     // page's scale factor, which can be 1 in use-zoom-for-dsf mode.
     if (!page())
         return 1;
 
     return page()->deviceScaleFactor();
 }
 
 } // namespace blink