Make cc::SurfaceId unguessable

cc/surfaces/display_unittest.cc

 // Copyright 2015 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/surfaces/display.h"
 
 #include <utility>
 
 #include "base/test/null_task_runner.h"
 #include "cc/output/compositor_frame.h"
@@ skipping 177 matching lines @@
   SetUpContext(nullptr);
   TestDisplayClient client;
   RendererSettings settings;
   settings.partial_swap_enabled = true;
   settings.finish_rendering_on_resize = true;
   TestDisplay display(&client, &manager_, shared_bitmap_manager_.get(), nullptr,
                       settings, id_allocator_.id_namespace());
   display.Initialize(std::move(output_surface_), task_runner_.get());
   TestDisplayScheduler& scheduler = display.scheduler();
 
-  SurfaceId surface_id(id_allocator_.GenerateId());
+  SurfaceId surface_id;
+  surface_id = id_allocator_.GenerateId();
   EXPECT_FALSE(scheduler.damaged);
   EXPECT_FALSE(scheduler.has_new_root_surface);
   display.SetSurfaceId(surface_id, 1.f);
   EXPECT_FALSE(scheduler.damaged);
   EXPECT_FALSE(scheduler.display_resized_);
   EXPECT_TRUE(scheduler.has_new_root_surface);
 
   scheduler.ResetDamageForTest();
   display.Resize(gfx::Size(100, 100));
   EXPECT_FALSE(scheduler.damaged);
@@ skipping 235 matching lines @@
   MOCK_METHOD0(shallowFinishCHROMIUM, void());
 };
 
 TEST_F(DisplayTest, Finish) {
   std::unique_ptr<MockedContext> context(new MockedContext());
   MockedContext* context_ptr = context.get();
   SetUpContext(std::move(context));
 
   EXPECT_CALL(*context_ptr, shallowFinishCHROMIUM()).Times(0);
 
-  SurfaceId surface_id(id_allocator_.GenerateId());
+  SurfaceId surface_id;
+  surface_id = id_allocator_.GenerateId();
 
   TestDisplayClient client;
   RendererSettings settings;
   settings.partial_swap_enabled = true;
   settings.finish_rendering_on_resize = true;
   TestDisplay display(&client, &manager_, shared_bitmap_manager_.get(), nullptr,
-                      settings, surface_id.id_namespace());
+                      settings, surface_id.id_namespace);
   display.Initialize(std::move(output_surface_), task_runner_.get());
 
   display.SetSurfaceId(surface_id, 1.f);
 
   display.Resize(gfx::Size(100, 100));
   factory_.Create(surface_id);
 
   {
     RenderPassList pass_list;
     std::unique_ptr<RenderPass> pass = RenderPass::Create();
@@ skipping 37 matching lines @@
 
   EXPECT_CALL(*context_ptr, shallowFinishCHROMIUM());
   display.Resize(gfx::Size(250, 250));
   testing::Mock::VerifyAndClearExpectations(context_ptr);
 
   factory_.Destroy(surface_id);
 }
 
 }  // namespace
 }  // namespace cc