Pass root ServerWindow id to FrameGenerator.

services/ui/ws/frame_generator_unittest.cc

 // Copyright 2016 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 "services/ui/ws/frame_generator.h"
 
 #include <memory>
 
 #include "base/test/test_message_loop.h"
 #include "cc/quads/render_pass.h"
 #include "cc/quads/shared_quad_state.h"
 #include "services/ui/surfaces/display_compositor.h"
+#include "services/ui/ws/ids.h"
 #include "services/ui/ws/platform_display_init_params.h"
 #include "services/ui/ws/server_window.h"
 #include "services/ui/ws/server_window_compositor_frame_sink_manager.h"
 #include "services/ui/ws/test_server_window_delegate.h"
 #include "services/ui/ws/test_utils.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace ui {
 namespace ws {
 namespace test {
 namespace {
 
+// Typical id for the display root ServerWindow.
+constexpr WindowId kRootDisplayId(0, 2);
+
 // Makes the window visible and creates the default surface for it.
 void InitWindow(ServerWindow* window) {
   window->SetVisible(true);
   ServerWindowCompositorFrameSinkManager* compositor_frame_sink_manager =
       window->GetOrCreateCompositorFrameSinkManager();
   compositor_frame_sink_manager->CreateCompositorFrameSink(
       mojom::CompositorFrameSinkType::DEFAULT,
       mojo::InterfaceRequest<cc::mojom::MojoCompositorFrameSink>(),
       cc::mojom::MojoCompositorFrameSinkClientPtr());
 }
@@ skipping 35 matching lines @@
                                    frame_generator_delegate_->GetRootWindow(),
                                    gfx::Vector2d(), 1.0f, nullptr);
 }
 
 void FrameGeneratorTest::SetUp() {
   testing::Test::SetUp();
   frame_generator_delegate_ = base::MakeUnique<TestFrameGeneratorDelegate>(
       base::MakeUnique<ServerWindow>(&window_delegate_, WindowId()));
   PlatformDisplayInitParams init_params;
   frame_generator_ = base::MakeUnique<FrameGenerator>(
-      frame_generator_delegate_.get(), display_compositor_);
+      frame_generator_delegate_.get(), kRootDisplayId, display_compositor_);
   InitWindow(root_window());
 }
 
 void FrameGeneratorTest::TearDown() {
   frame_generator_.reset();
   frame_generator_delegate_.reset();
 }
 
 // Tests correctness of the SharedQuadStateList generated by
 // FrameGenerator::DrawWindowTree().
@@ skipping 35 matching lines @@
   EXPECT_EQ(3u, quad_state_list->size());
   auto it = quad_state_list->begin();
   EXPECT_EQ(child_opacity * root_opacity, (*it)->opacity);
   EXPECT_EQ(child_opacity * root_opacity, (*++it)->opacity);
   EXPECT_EQ(root_opacity, (*++it)->opacity);
 }
 
 }  // namespace test
 }  // namespace ws
 }  // namespace ui