Teach GPU command buffer whether a context is webgl.

gpu/command_buffer/service/context_group.h

Index: gpu/command_buffer/service/context_group.h
diff --git a/gpu/command_buffer/service/context_group.h b/gpu/command_buffer/service/context_group.h
index 95cd4be2a92b9bc20c29d0fc0246c1a8ef97f8c6..5226aa10d6979643a41d48c5c737b263b52f5f96 100644
--- a/gpu/command_buffer/service/context_group.h
+++ b/gpu/command_buffer/service/context_group.h
@@ -44,6 +44,15 @@ struct DisallowedFeatures;
 // resources.
 class GPU_EXPORT ContextGroup : public base::RefCounted<ContextGroup> {
  public:
+  enum ContextType {
+    kContextTypeWebGL1,

[piman, 2015/06/09 02:19:37]

nit: CONTEXT_TYPE_WEBGL1 etc. per style guide.

[Zhenyao Mo, 2015/06/09 03:50:23]

Actually the new style guide prefers the constant style instead of the macro
style for enums:

http://google-styleguide.googlecode.com/svn/trunk/cppguide.html#Enumerator_Names

+    kContextTypeWebGL2,
+    kContextTypeOther,
+    kContextTypeUndefined
+  };
+
+  static ContextType GetContextType(unsigned webgl_version);
+
   ContextGroup(
       const scoped_refptr<MailboxManager>& mailbox_manager,
       const scoped_refptr<MemoryTracker>& memory_tracker,
@@ -57,6 +66,7 @@ class GPU_EXPORT ContextGroup : public base::RefCounted<ContextGroup> {
   // call to destroy if it succeeds.
   bool Initialize(
       GLES2Decoder* decoder,
+      ContextType context_type,
       const DisallowedFeatures& disallowed_features);
 
   // Destroys all the resources when called for the last context in the group.
@@ -249,6 +259,8 @@ class GPU_EXPORT ContextGroup : public base::RefCounted<ContextGroup> {
   bool QueryGLFeatureU(GLenum pname, GLint min_required, uint32* v);
   bool HaveContexts();
 
+  ContextType context_type_;
+
   scoped_refptr<MailboxManager> mailbox_manager_;
   scoped_refptr<MemoryTracker> memory_tracker_;
   scoped_refptr<ShaderTranslatorCache> shader_translator_cache_;