Hook ANGLE_request_extension up to the passthrough cmd decoder.

gpu/command_buffer/service/gles2_cmd_decoder_passthrough.cc

Index: gpu/command_buffer/service/gles2_cmd_decoder_passthrough.cc
diff --git a/gpu/command_buffer/service/gles2_cmd_decoder_passthrough.cc b/gpu/command_buffer/service/gles2_cmd_decoder_passthrough.cc
index ee25a045d89c983c3e2654c070ab45b51f25e3c6..16904721e07afe0faa62a5e6ff9ad1b5eb73e658 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder_passthrough.cc
+++ b/gpu/command_buffer/service/gles2_cmd_decoder_passthrough.cc
@@ -76,7 +76,7 @@ GLES2DecoderPassthroughImpl::GLES2DecoderPassthroughImpl(ContextGroup* group)
       surface_(),
       context_(),
       group_(group),
-      feature_info_(group->feature_info()) {
+      feature_info_(new FeatureInfo) {
   DCHECK(group);
 }
 
@@ -169,11 +169,22 @@ bool GLES2DecoderPassthroughImpl::Initialize(
     return false;
   }
 
+  // Each context initializes its own feature info because some extensions may
+  // be enabled dynamically

[Zhenyao Mo, 2017/02/06 22:31:38]

I am wondering if this is necessary - WebGL has no plans to share resources in
the near future, so basically WebGL will be in the one context per group
situation.

[Geoff Lang, 2017/02/07 19:01:15]

I wanted to be sure that the feature info doesn't get out of sync, I don't think
there is currently anything stopping a non-webgl context from calling
glRequestExtensionCHOMRIUM.  I could add an assert in DoRequestExtensionCHOMRIUM
that the context group only has one context or keep it as is, have a preference?

+  DisallowedFeatures adjusted_disallowed_features =
+      AdjustDisallowedFeatures(attrib_helper.context_type, disallowed_features);
+  if (!feature_info_->Initialize(attrib_helper.context_type,
+                                 adjusted_disallowed_features)) {
+    Destroy(true);
+    return false;
+  }
+
   // Check for required extensions
   if (!feature_info_->feature_flags().angle_robust_client_memory ||
-      !feature_info_->feature_flags().chromium_bind_generates_resource) {
-    // TODO(geofflang): Verify that ANGLE_webgl_compatibility is enabled if this
-    // is a WebGL context (depends on crbug.com/671217).
+      !feature_info_->feature_flags().chromium_bind_generates_resource ||
+      feature_info_->feature_flags().angle_webgl_compatibility !=
+          IsWebGLContextType(attrib_helper.context_type) ||
+      !feature_info_->feature_flags().angle_request_extension) {
     Destroy(true);
     return false;
   }