Merge 165866 - Disable threaded compositing when texture sharing is blacklisted

content/browser/gpu/compositor_util.cc

Index: content/browser/gpu/compositor_util.cc
===================================================================
--- content/browser/gpu/compositor_util.cc	(revision 165954)
+++ content/browser/gpu/compositor_util.cc	(working copy)
@@ -49,6 +49,15 @@
   if (!CanDoAcceleratedCompositing())
     return false;
 
+  const GpuDataManager* gpu_data_manager = GpuDataManager::GetInstance();
+  GpuFeatureType blacklisted_features =
+      gpu_data_manager->GetBlacklistedFeatures();
+  // Disallow threaded compositing when texture sharing is blacklisted since
+  // this triggers renderer-side readbacks for the thumbnailer / extensions.
+  // http://crbug.com/158747
+  if (blacklisted_features & GPU_FEATURE_TYPE_TEXTURE_SHARING)
+    return false;
+
   const CommandLine& command_line = *CommandLine::ForCurrentProcess();
 
   // Command line switches take precedence over field trials.