Make deferred image decoding default to on.

Source/web/WebSettingsImpl.cpp

 /*
  * Copyright (C) 2009 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 30 matching lines @@
 
 namespace blink {
 
 WebSettingsImpl::WebSettingsImpl(Settings* settings, DevToolsEmulator* devToolsEmulator)
     : m_settings(settings)
     , m_devToolsEmulator(devToolsEmulator)
     , m_showFPSCounter(false)
     , m_showPaintRects(false)
     , m_renderVSyncNotificationEnabled(false)
     , m_autoZoomFocusedNodeToLegibleScale(false)
-    , m_deferredImageDecodingEnabled(false)
     , m_supportDeprecatedTargetDensityDPI(false)
     , m_shrinksViewportContentToFit(false)
     , m_viewportMetaLayoutSizeQuirk(false)
     , m_viewportMetaNonUserScalableQuirk(false)
     , m_clobberUserAgentInitialScaleQuirk(false)
     , m_mainFrameResizesAreOrientationChanges(false)
 {
     ASSERT(settings);
 }
 
@@ skipping 478 matching lines @@
     m_settings->setAntialiased2dCanvasEnabled(enabled);
 }
 
 void WebSettingsImpl::setAntialiasedClips2dCanvasEnabled(bool enabled)
 {
     m_settings->setAntialiasedClips2dCanvasEnabled(enabled);
 }
 
 void WebSettingsImpl::setDeferredImageDecodingEnabled(bool enabled)
 {
-    DeferredImageDecoder::setEnabled(enabled);
-    m_deferredImageDecodingEnabled = enabled;
 }
 
 void WebSettingsImpl::setPreferCompositingToLCDTextEnabled(bool enabled)
 {
     m_devToolsEmulator->setPreferCompositingToLCDTextEnabled(enabled);
 }
 
 void WebSettingsImpl::setMinimumAccelerated2dCanvasSize(int numPixels)
 {
     m_settings->setMinimumAccelerated2dCanvasSize(numPixels);
@@ skipping 229 matching lines @@
 {
     m_settings->setV8CacheOptions(static_cast<blink::V8CacheOptions>(options));
 }
 
 void WebSettingsImpl::setUseMobileViewportStyle(bool enabled)
 {
     m_devToolsEmulator->setUseMobileViewportStyle(enabled);
 }
 
 } // namespace blink