Expose --disable-gpu-compositing browser arg to Blink

content/child/runtime_features.cc

Index: content/child/runtime_features.cc
diff --git a/content/child/runtime_features.cc b/content/child/runtime_features.cc
index 487fc375e170d4022cd337d57c1fdd0e932dcaaa..5eb2ea8e94fff4d2c10ed4761195885859966ba4 100644
--- a/content/child/runtime_features.cc
+++ b/content/child/runtime_features.cc
@@ -115,6 +115,12 @@ void SetRuntimeFeaturesDefaultsAndUpdateFromArgs(
   if (command_line.HasSwitch(switches::kForceDisplayList2dCanvas))
     WebRuntimeFeatures::forceDisplayList2dCanvas(true);
 
+  if (command_line.HasSwitch(switches::kDisableGpuCompositing) ||
+      command_line.HasSwitch(switches::kDisableGpu))

[danakj, 2016/10/04 21:41:27]

Sorry just noticed this but you don't need to check disable-gpu here. In that
case we won't be able to make a context. Similarly we dont check for that flag
here
https://cs.chromium.org/chromium/src/content/renderer/render_thread_impl.cc?r...

+    WebRuntimeFeatures::enableGpuCompositing(false);
+  else
+    WebRuntimeFeatures::enableGpuCompositing(true);
+
   if (command_line.HasSwitch(
       switches::kEnableCanvas2dDynamicRenderingModeSwitching))
     WebRuntimeFeatures::enableCanvas2dDynamicRenderingModeSwitching(true);