Make chrome --mus run the UI Service inside the browser process.

This CL takes advantage of the mechanisms introduced in
https://codereview.chromium.org/2979933002/ to run the UI Service inside the
browser process in Mushrome (i.e. when chrome is launched with --mus parameter).

UI Service runs on a separate thread with high priority. For now both the UI
Service and the GPU Service are moved. Once WS/GPU split if finished, GPU will
need to be moved into its separate process.

CrOS BrowserProcessPlatformPart owns the ImageCursorsSet used by the UI Service
for cursor manipulation.

BUG=722527

Review-Url: https://codereview.chromium.org/2983443002
Cr-Commit-Position: refs/heads/master@{#486688}

chrome/app/BUILD.gn

@@ -408,7 +408,10 @@ service_manifest("chrome_content_packaged_services_manifest_overlay") {
       "//chrome/browser/chrome_content_packaged_services_manifest_overlay.json"
   packaged_services = chrome_packaged_services
   if (is_chromeos) {
-    packaged_services += [ "//ash/mus:manifest" ]
+    packaged_services += [
+      "//ash/mus:manifest",
+      "//services/ui:manifest",
+    ]
   }
 }
 

chrome/app/mash/BUILD.gn

@@ -122,8 +122,6 @@ if (is_chromeos) {
   catalog("catalog_mus") {
     catalog_deps = [ "//chrome/app:catalog" ]
     embedded_services = [
-      "//services/ui:manifest",
-
       # TODO(sky): verify if we need this.
       "//services/ui/ime/test_ime_driver:manifest",
     ]

chrome/browser/DEPS

@@ -53,7 +53,9 @@ include_rules = [
   "+services/resource_coordinator/public/interfaces/memory_instrumentation",
   "+services/service_manager",
   "+services/shape_detection/public/interfaces",
+  "+services/ui/common",
   "+services/ui/public",
+  "+services/ui/service.h",
   "+skia/ext",
   "+third_party/boringssl/src/include",
   "+third_party/crashpad",

chrome/browser/browser_process_platform_part_chromeos.cc

@@ -44,6 +44,7 @@
 #include "services/service_manager/public/cpp/interface_provider.h"
 #include "services/service_manager/public/cpp/service.h"
 #include "services/ui/public/interfaces/constants.mojom.h"
+#include "services/ui/service.h"
 
 #if defined(USE_OZONE)
 #include "content/public/common/service_manager_connection.h"
@@ -129,6 +130,15 @@ class ChromeServiceChromeOS : public service_manager::Service,
   DISALLOW_COPY_AND_ASSIGN(ChromeServiceChromeOS);
 };
 
+std::unique_ptr<service_manager::Service> CreateEmbeddedUIService(
+    const scoped_refptr<base::SingleThreadTaskRunner>& task_runner,
+    base::WeakPtr<ui::ImageCursorsSet> image_cursors_set_weak_ptr) {
+  ui::Service::InProcessConfig config;
+  config.resource_runner = task_runner;
+  config.image_cursors_set_weak_ptr = image_cursors_set_weak_ptr;
+  return base::MakeUnique<ui::Service>(&config);
+}
+
 }  // namespace
 
 BrowserProcessPlatformPart::BrowserProcessPlatformPart()
@@ -274,6 +284,17 @@ void BrowserProcessPlatformPart::RegisterInProcessServices(
     info.task_runner = base::ThreadTaskRunnerHandle::Get();
     services->insert(std::make_pair(ash::mojom::kServiceName, info));
   }
+
+  if (chromeos::GetAshConfig() == ash::Config::MUS) {
+    service_manager::EmbeddedServiceInfo info;
+    info.factory = base::Bind(&CreateEmbeddedUIService,
+                              base::ThreadTaskRunnerHandle::Get(),
+                              image_cursors_set_.GetWeakPtr());
+    info.use_own_thread = true;
+    info.message_loop_type = base::MessageLoop::TYPE_UI;
+    info.thread_priority = base::ThreadPriority::DISPLAY;
+    services->insert(std::make_pair(ui::mojom::kServiceName, info));
+  }
 }
 
 chromeos::system::SystemClock* BrowserProcessPlatformPart::GetSystemClock() {

chrome/browser/browser_process_platform_part_chromeos.h

@@ -13,6 +13,7 @@
 #include "base/macros.h"
 #include "base/sequence_checker.h"
 #include "chrome/browser/browser_process_platform_part_base.h"
+#include "services/ui/common/image_cursors_set.h"
 
 namespace chromeos {
 class ChromeSessionManager;
@@ -140,6 +141,9 @@ class BrowserProcessPlatformPart : public BrowserProcessPlatformPartBase {
 
   base::flat_set<std::string> compatible_cros_components_;
 
+  // Used by the UI Service.
+  ui::ImageCursorsSet image_cursors_set_;
+
 #if defined(USE_OZONE)
   std::unique_ptr<ui::InputDeviceControllerClient>
       input_device_controller_client_;