Expose mapExternalTexture extension to WebGraphicsContext3D

webkit/gpu/webgraphicscontext3d_in_process_command_buffer_impl.cc

Index: webkit/gpu/webgraphicscontext3d_in_process_command_buffer_impl.cc
diff --git a/webkit/gpu/webgraphicscontext3d_in_process_command_buffer_impl.cc b/webkit/gpu/webgraphicscontext3d_in_process_command_buffer_impl.cc
index 937fdb772742c11919c10329c04892894aaccf78..66e8ee8ae3cdc517c9281446e822c696b15fa044 100644
--- a/webkit/gpu/webgraphicscontext3d_in_process_command_buffer_impl.cc
+++ b/webkit/gpu/webgraphicscontext3d_in_process_command_buffer_impl.cc
@@ -967,6 +967,18 @@ void WebGraphicsContext3DInProcessCommandBufferImpl::
   copyTextureToCompositor(texture, parentTexture);
 }
 
+void WebGraphicsContext3DInProcessCommandBufferImpl::mapExternalTextureCHROMIUM(
+      WebGLId source_texture, WebGraphicsContext3D* source_context,
+      WebGLId destination_texture) {
+  WebGraphicsContext3DInProcessCommandBufferImpl* source_cmdbuffer_context =
+      static_cast<WebGraphicsContext3DInProcessCommandBufferImpl*>(
+          source_context);
+  context_->MapExternalResource(::gpu::resource_type::kTexture,
+                                source_texture,
+                                source_cmdbuffer_context->context(),
+                                destination_texture);
+}
+
 void WebGraphicsContext3DInProcessCommandBufferImpl::
     rateLimitOffscreenContextCHROMIUM() {
   // TODO(gmam): See if we can comment this in.