Move bindToCurrentThread out to the creators of WebGL contexts.

content/renderer/webgraphicscontext3d_provider_impl.h

Index: content/renderer/webgraphicscontext3d_provider_impl.h
diff --git a/content/renderer/webgraphicscontext3d_provider_impl.h b/content/renderer/webgraphicscontext3d_provider_impl.h
index 6196b24ba4133b201c253a5f3812e0e36a49ed67..c5f681c169884515833867a3efa3ca6ee3173a19 100644
--- a/content/renderer/webgraphicscontext3d_provider_impl.h
+++ b/content/renderer/webgraphicscontext3d_provider_impl.h
@@ -27,6 +27,7 @@ class CONTENT_EXPORT WebGraphicsContext3DProviderImpl
   ~WebGraphicsContext3DProviderImpl() override;
 
   // WebGraphicsContext3DProvider implementation.
+  bool bindToCurrentThread() override;
   gpu::gles2::GLES2Interface* contextGL() override;
   GrContext* grContext() override;
   gpu::Capabilities getCapabilities() override;
@@ -38,8 +39,6 @@ class CONTENT_EXPORT WebGraphicsContext3DProviderImpl
     return provider_.get();
   }
 
-  bool bindToCurrentThread() override;
-
  private:
   scoped_refptr<ContextProviderCommandBuffer> provider_;
 };