cc: Make PrepareToDraw return an enum for why it aborts

cc/output/delegating_renderer_unittest.cc

 // Copyright 2013 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/output/delegating_renderer.h"
 
 #include "cc/test/fake_output_surface.h"
 #include "cc/test/layer_tree_test.h"
 #include "cc/test/render_pass_test_common.h"
 #include "cc/test/render_pass_test_utils.h"
@@ skipping 21 matching lines @@
 
 class DelegatingRendererTestDraw : public DelegatingRendererTest {
  public:
   virtual void BeginTest() OVERRIDE {
     layer_tree_host()->SetPageScaleFactorAndLimits(1.f, 0.5f, 4.f);
     PostSetNeedsCommitToMainThread();
   }
 
   virtual void AfterTest() OVERRIDE {}
 
-  virtual bool PrepareToDrawOnThread(LayerTreeHostImpl* host_impl,
-                                     LayerTreeHostImpl::FrameData* frame,
-                                     bool result)
-      OVERRIDE {
+  virtual DrawSwapReadbackResult::DrawResult PrepareToDrawOnThread(
+      LayerTreeHostImpl* host_impl,
+      LayerTreeHostImpl::FrameData* frame,
+      DrawSwapReadbackResult::DrawResult draw_result) OVERRIDE {
     EXPECT_EQ(0u, output_surface_->num_sent_frames());
 
     const CompositorFrame& last_frame = output_surface_->last_sent_frame();
     EXPECT_FALSE(last_frame.delegated_frame_data);
     EXPECT_FALSE(last_frame.gl_frame_data);
     EXPECT_EQ(0.f, last_frame.metadata.min_page_scale_factor);
     EXPECT_EQ(0.f, last_frame.metadata.max_page_scale_factor);
-    return true;
+    return DrawSwapReadbackResult::DID_DRAW;
   }
 
   virtual void DrawLayersOnThread(LayerTreeHostImpl* host_impl) OVERRIDE {
     EXPECT_EQ(0u, output_surface_->num_sent_frames());
   }
 
   virtual void SwapBuffersOnThread(LayerTreeHostImpl* host_impl,
                                    bool result) OVERRIDE {
     EXPECT_TRUE(result);
     EXPECT_EQ(1u, output_surface_->num_sent_frames());
@@ skipping 18 matching lines @@
 SINGLE_AND_MULTI_THREAD_DELEGATING_RENDERER_TEST_F(DelegatingRendererTestDraw);
 
 class DelegatingRendererTestResources : public DelegatingRendererTest {
  public:
   virtual void BeginTest() OVERRIDE {
     PostSetNeedsCommitToMainThread();
   }
 
   virtual void AfterTest() OVERRIDE {}
 
-  virtual bool PrepareToDrawOnThread(
+  virtual DrawSwapReadbackResult::DrawResult PrepareToDrawOnThread(
       LayerTreeHostImpl* host_impl,
       LayerTreeHostImpl::FrameData* frame,
-      bool result) OVERRIDE {
+      DrawSwapReadbackResult::DrawResult draw_result) OVERRIDE {
     frame->render_passes.clear();
     frame->render_passes_by_id.clear();
 
     TestRenderPass* child_pass = AddRenderPass(
         &frame->render_passes,
         RenderPass::Id(2, 1),
         gfx::Rect(3, 3, 10, 10),
         gfx::Transform());
     child_pass->AppendOneOfEveryQuadType(
         host_impl->resource_provider(), RenderPass::Id(0, 0));
 
     TestRenderPass* pass = AddRenderPass(
         &frame->render_passes,
         RenderPass::Id(1, 1),
         gfx::Rect(3, 3, 10, 10),
         gfx::Transform());
     pass->AppendOneOfEveryQuadType(
         host_impl->resource_provider(), child_pass->id);
-    return true;
+    return DrawSwapReadbackResult::DID_DRAW;
   }
 
   virtual void DrawLayersOnThread(LayerTreeHostImpl* host_impl) OVERRIDE {
     EXPECT_EQ(0u, output_surface_->num_sent_frames());
   }
 
   virtual void SwapBuffersOnThread(LayerTreeHostImpl* host_impl,
                                    bool result) OVERRIDE {
     EXPECT_TRUE(result);
     EXPECT_EQ(1u, output_surface_->num_sent_frames());
@@ skipping 11 matching lines @@
         22u, last_frame.delegated_frame_data->resource_list.size());
 
     EndTest();
   }
 };
 
 SINGLE_AND_MULTI_THREAD_DELEGATING_RENDERER_TEST_F(
     DelegatingRendererTestResources);
 
 }  // namespace cc