Remove offscreen compositor contexts.

cc/test/fake_layer_tree_host_client.cc

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/test/fake_layer_tree_host_client.h"
 
 #include "cc/output/context_provider.h"
 #include "cc/test/fake_output_surface.h"
 #include "cc/test/test_web_graphics_context_3d.h"
 
@@ skipping 17 matching lines @@
 
     return FakeOutputSurface::CreateSoftware(
         make_scoped_ptr(new SoftwareOutputDevice)).PassAs<OutputSurface>();
   }
 
   if (use_delegating_renderer_)
     return FakeOutputSurface::CreateDelegating3d().PassAs<OutputSurface>();
   return FakeOutputSurface::Create3d().PassAs<OutputSurface>();
 }
 
-scoped_refptr<ContextProvider>
-FakeLayerTreeHostClient::OffscreenContextProvider() {
-  if (!offscreen_contexts_.get() ||
-      offscreen_contexts_->DestroyedOnMainThread())
-    offscreen_contexts_ = TestContextProvider::Create();
-  return offscreen_contexts_;
-}
-
 }  // namespace cc