services/ui: Use a gpu::GpuChannelHost when creating ui::OutputSurface.

services/ui/demo/bitmap_uploader.cc

Index: services/ui/demo/bitmap_uploader.cc
diff --git a/services/ui/demo/bitmap_uploader.cc b/services/ui/demo/bitmap_uploader.cc
index 204b952f54a4ec5da63713889e14ebd780034921..03550d2334c334aa6ba61ce3f70ce38668db7f12 100644
--- a/services/ui/demo/bitmap_uploader.cc
+++ b/services/ui/demo/bitmap_uploader.cc
@@ -14,6 +14,7 @@
 #include "cc/quads/solid_color_draw_quad.h"
 #include "cc/quads/texture_draw_quad.h"
 #include "services/ui/public/cpp/gles2_context.h"
+#include "services/ui/public/cpp/gpu_service.h"
 #include "services/ui/public/cpp/window.h"
 #include "services/ui/public/cpp/window_surface.h"
 
@@ -29,25 +30,22 @@ const char kBitmapUploaderForAcceleratedWidget[] =
 
 BitmapUploader::BitmapUploader(Window* window, GpuService* gpu_service)
     : window_(window),
-      gpu_service_(gpu_service),
       color_(g_transparent_color),
       width_(0),
       height_(0),
       format_(BGRA),
-      next_resource_id_(1u) {}
-
-BitmapUploader::~BitmapUploader() {
-}
-
-void BitmapUploader::Init() {
+      next_resource_id_(1u) {
   surface_ = window_->RequestSurface(mojom::SurfaceType::DEFAULT);
   surface_->BindToThread();
   surface_->set_client(this);
 
-  gles2_context_ = GLES2Context::CreateOffscreenContext(gpu_service_);
+  gles2_context_ = GLES2Context::CreateOffscreenContext(
+      gpu_service->EstablishGpuChannelSync());

[sky, 2016/08/18 13:15:45]

Aren't these all rather expensive calls? Seems like an Init() better matches the
style guide.

[sadrul, 2016/08/18 14:59:48]

Done.

   // CreateOffscreenContext() may return null.

[sky, 2016/08/18 13:15:45]

Update or remove comment?

[sadrul, 2016/08/18 14:59:48]

Done (removed)

 }
 
+BitmapUploader::~BitmapUploader() {}
+
 // Sets the color which is RGBA.
 void BitmapUploader::SetColor(uint32_t color) {
   if (color_ == color)