Add Blink-side flag for enabling/disabling layer squashing.

Source/core/testing/InternalSettings.cpp

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  * Copyright (C) 2013 Apple 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:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
@@ skipping 57 matching lines @@
     , m_originalAccessibilityFontScaleFactor(settings->accessibilityFontScaleFactor())
     , m_originalMediaTypeOverride(settings->mediaTypeOverride())
     , m_originalMockScrollbarsEnabled(settings->mockScrollbarsEnabled())
     , m_langAttributeAwareFormControlUIEnabled(RuntimeEnabledFeatures::langAttributeAwareFormControlUIEnabled())
     , m_imagesEnabled(settings->areImagesEnabled())
     , m_shouldDisplaySubtitles(settings->shouldDisplaySubtitles())
     , m_shouldDisplayCaptions(settings->shouldDisplayCaptions())
     , m_shouldDisplayTextDescriptions(settings->shouldDisplayTextDescriptions())
     , m_defaultVideoPosterURL(settings->defaultVideoPosterURL())
     , m_originalCompositorDrivenAcceleratedScrollEnabled(settings->isCompositorDrivenAcceleratedScrollingEnabled())
+    , m_originalLayerSquashingEnabled(settings->isLayerSquashingEnabled())
     , m_originalPasswordGenerationDecorationEnabled(settings->passwordGenerationDecorationEnabled())
 {
 }
 
 void InternalSettings::Backup::restoreTo(Settings* settings)
 {
     RuntimeEnabledFeatures::setCSSExclusionsEnabled(m_originalCSSExclusionsEnabled);
     RuntimeEnabledFeatures::setAuthorShadowDOMForAnyElementEnabled(m_originalAuthorShadowDOMForAnyElementEnabled);
     settings->setExperimentalWebSocketEnabled(m_originalExperimentalWebSocketEnabled);
     RuntimeEnabledFeatures::setStyleScopedEnabled(m_originalStyleScoped);
     RuntimeEnabledFeatures::setOverlayScrollbarsEnabled(m_originalOverlayScrollbarsEnabled);
     settings->setEditingBehaviorType(m_originalEditingBehavior);
     settings->setTextAutosizingEnabled(m_originalTextAutosizingEnabled);
     settings->setTextAutosizingWindowSizeOverride(m_originalTextAutosizingWindowSizeOverride);
     settings->setAccessibilityFontScaleFactor(m_originalAccessibilityFontScaleFactor);
     settings->setMediaTypeOverride(m_originalMediaTypeOverride);
     settings->setMockScrollbarsEnabled(m_originalMockScrollbarsEnabled);
     RuntimeEnabledFeatures::setLangAttributeAwareFormControlUIEnabled(m_langAttributeAwareFormControlUIEnabled);
     settings->setImagesEnabled(m_imagesEnabled);
     settings->setShouldDisplaySubtitles(m_shouldDisplaySubtitles);
     settings->setShouldDisplayCaptions(m_shouldDisplayCaptions);
     settings->setShouldDisplayTextDescriptions(m_shouldDisplayTextDescriptions);
     settings->setDefaultVideoPosterURL(m_defaultVideoPosterURL);
     settings->setCompositorDrivenAcceleratedScrollingEnabled(m_originalCompositorDrivenAcceleratedScrollEnabled);
+    settings->setLayerSquashingEnabled(m_originalLayerSquashingEnabled);
     settings->setPasswordGenerationDecorationEnabled(m_originalPasswordGenerationDecorationEnabled);
     settings->resetFontFamilies();
 }
 
 // We can't use RefCountedSupplement because that would try to make InternalSettings RefCounted
 // and InternalSettings is already RefCounted via its base class, InternalSettingsGenerated.
 // Instead, we manually make InternalSettings supplement Page.
 class InternalSettingsWrapper : public Supplement<Page> {
 public:
     explicit InternalSettingsWrapper(Page* page)
@@ skipping 87 matching lines @@
 }
 
 // FIXME: This is a temporary flag and should be removed once accelerated
 // overflow scroll is ready (crbug.com/254111).
 void InternalSettings::setCompositorDrivenAcceleratedScrollingEnabled(bool enabled, ExceptionState& exceptionState)
 {
     InternalSettingsGuardForSettings();
     settings()->setCompositorDrivenAcceleratedScrollingEnabled(enabled);
 }
 
+// FIXME: This is a temporary flag and should be removed once squashing is
+// ready (crbug.com/261605).
+void InternalSettings::setLayerSquashingEnabled(bool enabled, ExceptionState& exceptionState)
+{
+    InternalSettingsGuardForSettings();
+    settings()->setLayerSquashingEnabled(enabled);
+}
+
 typedef void (Settings::*SetFontFamilyFunction)(const AtomicString&, UScriptCode);
 static void setFontFamily(Settings* settings, const String& family, const String& script, SetFontFamilyFunction setter)
 {
     UScriptCode code = scriptNameToCode(script);
     if (code != USCRIPT_INVALID_CODE)
         (settings->*setter)(family, code);
 }
 
 void InternalSettings::setStandardFontFamily(const String& family, const String& script, ExceptionState& exceptionState)
 {
@@ skipping 98 matching lines @@
     settings()->setDefaultVideoPosterURL(url);
 }
 
 void InternalSettings::setPasswordGenerationDecorationEnabled(bool enabled, ExceptionState& exceptionState)
 {
     InternalSettingsGuardForSettings();
     settings()->setPasswordGenerationDecorationEnabled(enabled);
 }
 
 }