mus: Changes SetDisplayRoot() to create actual display

services/ui/service.cc

 // Copyright 2014 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/service.h"
 
 #include <set>
 
 #include "base/bind.h"
 #include "base/command_line.h"
@@ skipping 24 matching lines @@
 #include "services/ui/ws/user_display_manager.h"
 #include "services/ui/ws/window_server.h"
 #include "services/ui/ws/window_server_test_impl.h"
 #include "services/ui/ws/window_tree.h"
 #include "services/ui/ws/window_tree_binding.h"
 #include "services/ui/ws/window_tree_factory.h"
 #include "services/ui/ws/window_tree_host_factory.h"
 #include "ui/base/platform_window_defaults.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/base/ui_base_paths.h"
+#include "ui/display/screen_base.h"
 #include "ui/events/event_switches.h"
 #include "ui/events/platform/platform_event_source.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gl/gl_surface.h"
 
 #if defined(USE_X11)
 #include <X11/Xlib.h>
 #include "ui/base/x/x11_util.h"  // nogncheck
 #include "ui/platform_window/x11/x11_window.h"
 #elif defined(USE_OZONE)
+#include "services/ui/display/screen_manager_forwarding.h"
 #include "ui/events/ozone/layout/keyboard_layout_engine.h"
 #include "ui/events/ozone/layout/keyboard_layout_engine_manager.h"
 #include "ui/ozone/public/ozone_platform.h"
 #endif
 
 using mojo::InterfaceRequest;
 using ui::mojom::WindowServerTest;
 using ui::mojom::WindowTreeHostFactory;
 
 namespace ui {
@@ skipping 14 matching lines @@
 };
 
 struct Service::UserState {
   std::unique_ptr<clipboard::ClipboardImpl> clipboard;
   std::unique_ptr<ws::AccessibilityManager> accessibility;
   std::unique_ptr<ws::WindowTreeHostFactory> window_tree_host_factory;
 };
 
 Service::Service()
     : test_config_(false),
-      screen_manager_(display::ScreenManager::Create()),
       ime_registrar_(&ime_server_) {}
 
 Service::~Service() {
   // Destroy |window_server_| first, since it depends on |event_source_|.
   // WindowServer (or more correctly its Displays) may have state that needs to
   // be destroyed before GpuState as well.
   window_server_.reset();
 
 #if defined(USE_OZONE)
   OzonePlatform::Shutdown();
 #endif
+
+  if (screen_)
+    display::Screen::SetScreenInstance(nullptr);
 }
 
 void Service::InitializeResources(service_manager::Connector* connector) {
   if (ui::ResourceBundle::HasSharedInstance())
     return;
 
   std::set<std::string> resource_paths;
   resource_paths.insert(kResourceFileStrings);
   resource_paths.insert(kResourceFile100);
   resource_paths.insert(kResourceFile200);
@@ skipping 102 matching lines @@
       .AddInterface<discardable_memory::mojom::DiscardableSharedMemoryManager>(
           this);
   if (test_config_)
     registry_.AddInterface<WindowServerTest>(this);
 
   // On non-Linux platforms there will be no DeviceDataManager instance and no
   // purpose in adding the Mojo interface to connect to.
   if (input_device_server_.IsRegisteredAsObserver())
     input_device_server_.AddInterface(&registry_);
 
-  screen_manager_->AddInterfaces(&registry_);
-
 #if defined(USE_OZONE)
   ui::OzonePlatform::GetInstance()->AddInterfaces(&registry_);
 #endif
 }
 
 void Service::OnBindInterface(const service_manager::ServiceInfo& source_info,
                               const std::string& interface_name,
                               mojo::ScopedMessagePipeHandle interface_pipe) {
   registry_.BindInterface(source_info.identity, interface_name,
                           std::move(interface_pipe));
 }
 
 void Service::StartDisplayInit() {
-  screen_manager_->Init(window_server_->display_manager());
+  DCHECK(!is_gpu_ready_);  // This should only be called once.
+  is_gpu_ready_ = true;
+  if (screen_manager_)
+    screen_manager_->Init(window_server_->display_manager());
 }
 
 void Service::OnFirstDisplayReady() {
   PendingRequests requests;
   requests.swap(pending_requests_);
   for (auto& request : requests) {
     if (request->wtf_request)
       Create(request->remote_identity, std::move(*request->wtf_request));
     else
       Create(request->remote_identity, std::move(*request->dm_request));
   }
 }
 
 void Service::OnNoMoreDisplays() {
   // We may get here from the destructor, in which case there is no messageloop.
   if (base::MessageLoop::current() &&
       base::MessageLoop::current()->is_running()) {
     base::MessageLoop::current()->QuitWhenIdle();
   }
 }
 
 bool Service::IsTestConfig() const {
   return test_config_;
 }
 
+void Service::OnWillCreateTreeForWindowManager(

[kylechar, 2017/04/19 18:06:08]

What's the expected order that StartDisplayInit() vs
OnWillCreateTreeForWindowManager() getting called? They can happen in any order
it looks like?

[sky, 2017/04/19 19:30:03]

You are correct. One is not guaranteed to be called before the other.

+    bool automatically_create_display_roots) {
+  if (screen_manager_config_ != ScreenManagerConfig::UNKNOWN)
+    return;
+
+  DVLOG(3) << "OnWillCreateTreeForWindowManager "
+           << automatically_create_display_roots;
+  screen_manager_config_ = automatically_create_display_roots
+                               ? ScreenManagerConfig::INTERNAL
+                               : ScreenManagerConfig::FORWARDING;
+  if (screen_manager_config_ == ScreenManagerConfig::FORWARDING) {
+    screen_ = base::MakeUnique<display::ScreenBase>();
+    display::Screen::SetScreenInstance(screen_.get());
+#if defined(USE_OZONE)
+    screen_manager_ = base::MakeUnique<display::ScreenManagerForwarding>();
+#else
+    CHECK(false);
+#endif
+  } else {
+    screen_manager_ = display::ScreenManager::Create();
+  }
+  screen_manager_->AddInterfaces(&registry_);
+  if (is_gpu_ready_)
+    screen_manager_->Init(window_server_->display_manager());
+}
+
+display::ScreenBase* Service::GetScreen() {
+  return screen_.get();
+}
+
 void Service::Create(const service_manager::Identity& remote_identity,
                      mojom::AccessibilityManagerRequest request) {
   UserState* user_state = GetUserState(remote_identity);
   if (!user_state->accessibility) {
     const ws::UserId& user_id = remote_identity.user_id();
     user_state->accessibility.reset(
         new ws::AccessibilityManager(window_server_.get(), user_id));
   }
   user_state->accessibility->Bind(std::move(request));
 }
@@ skipping 95 matching lines @@
                      mojom::WindowServerTestRequest request) {
   if (!test_config_)
     return;
   mojo::MakeStrongBinding(
       base::MakeUnique<ws::WindowServerTestImpl>(window_server_.get()),
       std::move(request));
 }
 
 
 }  // namespace ui