Promote RenderLayers that have a transition on opacity, transform, or filter

Tools/DumpRenderTree/chromium/TestRunner/src/WebPreferences.cpp

Index: Tools/DumpRenderTree/chromium/TestRunner/src/WebPreferences.cpp
diff --git a/Tools/DumpRenderTree/chromium/TestRunner/src/WebPreferences.cpp b/Tools/DumpRenderTree/chromium/TestRunner/src/WebPreferences.cpp
index 335f935eb06156a0adcc6350b254f26a2f2c5a16..b4f2a2bd154f75d7c298a12b3a0c4b8cb8025e69 100644
--- a/Tools/DumpRenderTree/chromium/TestRunner/src/WebPreferences.cpp
+++ b/Tools/DumpRenderTree/chromium/TestRunner/src/WebPreferences.cpp
@@ -116,6 +116,7 @@ void WebPreferences::reset()
     acceleratedCompositingForVideoEnabled = false;
     acceleratedCompositingForFixedPositionEnabled = false;
     acceleratedCompositingForOverflowScrollEnabled = false;
+    acceleratedCompositingForTransitionEnabled = false;
     acceleratedCompositingEnabled = false;
     accelerated2dCanvasEnabled = false;
     forceCompositingMode = false;
@@ -182,6 +183,7 @@ void WebPreferences::applyTo(WebView* webView)
     settings->setAcceleratedCompositingForVideoEnabled(acceleratedCompositingForVideoEnabled);
     settings->setAcceleratedCompositingForFixedPositionEnabled(acceleratedCompositingForFixedPositionEnabled);
     settings->setAcceleratedCompositingForOverflowScrollEnabled(acceleratedCompositingForOverflowScrollEnabled);
+    settings->setAcceleratedCompositingForTransitionEnabled(acceleratedCompositingForTransitionEnabled);
     settings->setFixedPositionCreatesStackingContext(acceleratedCompositingForFixedPositionEnabled);
     settings->setForceCompositingMode(forceCompositingMode);
     settings->setThreadedHTMLParser(threadedHTMLParser);