Revert of Revert of Revert of Enable display list 2D canvas by default

content/child/runtime_features.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/child/runtime_features.h"
 
 #include "base/command_line.h"
 #include "base/metrics/field_trial.h"
 #include "content/common/content_switches_internal.h"
 #include "content/public/common/content_switches.h"
@@ skipping 127 matching lines @@
 
   if (command_line.HasSwitch(switches::kDisableFileSystem))
     WebRuntimeFeatures::enableFileSystem(false);
 
   if (command_line.HasSwitch(switches::kEnableExperimentalCanvasFeatures))
     WebRuntimeFeatures::enableExperimentalCanvasFeatures(true);
 
   if (command_line.HasSwitch(switches::kEnableAcceleratedJpegDecoding))
     WebRuntimeFeatures::enableDecodeToYUV(true);
 
-  if (command_line.HasSwitch(switches::kEnableDisplayList2dCanvas))
+  if (command_line.HasSwitch(switches::kDisableDisplayList2dCanvas)) {
+    WebRuntimeFeatures::enableDisplayList2dCanvas(false);
+  } else if (command_line.HasSwitch(switches::kForceDisplayList2dCanvas)) {
+    WebRuntimeFeatures::forceDisplayList2dCanvas(true);
+  } else if (command_line.HasSwitch(switches::kEnableDisplayList2dCanvas)) {
     WebRuntimeFeatures::enableDisplayList2dCanvas(true);
-
-  if (command_line.HasSwitch(switches::kDisableDisplayList2dCanvas))
-    WebRuntimeFeatures::enableDisplayList2dCanvas(false);
-
-  if (command_line.HasSwitch(switches::kForceDisplayList2dCanvas))
-    WebRuntimeFeatures::forceDisplayList2dCanvas(true);
+  } else {
+    WebRuntimeFeatures::enableDisplayList2dCanvas(
+        base::FieldTrialList::FindFullName("DisplayList2dCanvas") == "Enabled"
+    );
+  }
 
   if (command_line.HasSwitch(switches::kEnableWebGLDraftExtensions))
     WebRuntimeFeatures::enableWebGLDraftExtensions(true);
 
   if (command_line.HasSwitch(switches::kEnableWebGLImageChromium))
     WebRuntimeFeatures::enableWebGLImageChromium(true);
 
   if (command_line.HasSwitch(switches::kEnableOverlayFullscreenVideo))
     WebRuntimeFeatures::enableOverlayFullscreenVideo(true);
 
@@ skipping 17 matching lines @@
 
   if (command_line.HasSwitch(switches::kDisableSVG1DOM)) {
     WebRuntimeFeatures::enableSVG1DOM(false);
   }
 
   if (command_line.HasSwitch(switches::kReducedReferrerGranularity))
     WebRuntimeFeatures::enableReducedReferrerGranularity(true);
 }
 
 }  // namespace content