Add support to the UI Service to run it inside the browser's process.

services/ui/service.h

Index: services/ui/service.h
diff --git a/services/ui/service.h b/services/ui/service.h
index 4d035f9c94a2d269df23c1d455a7e5f68f796044..a2e08883b53b1c9fbdfcef711c4be09cbae0e30b 100644
--- a/services/ui/service.h
+++ b/services/ui/service.h
@@ -13,6 +13,8 @@
 #include <vector>
 
 #include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "base/memory/weak_ptr.h"
 #include "components/discardable_memory/public/interfaces/discardable_shared_memory_manager.mojom.h"
 #include "services/service_manager/public/cpp/binder_registry.h"
 #include "services/service_manager/public/cpp/service.h"
@@ -53,17 +55,37 @@ class Identity;
 
 namespace ui {
 
+class ImageCursorsSet;
 class InputDeviceController;
 class PlatformEventSource;
 
 namespace ws {
+class ThreadedImageCursorsFactory;
 class WindowServer;
 }
 
 class Service : public service_manager::Service,
                 public ws::WindowServerDelegate {
  public:
-  Service();
+  // Contains the configuration necessary to run the UI Service inside the
+  // Window Manager's process.
+  struct InProcessConfig {
+    InProcessConfig();
+    ~InProcessConfig();
+
+    // Can be used to load resources.
+    scoped_refptr<base::SingleThreadTaskRunner> resource_runner = nullptr;
+
+    // Can only be de-referenced on |resource_runner_|.
+    base::WeakPtr<ImageCursorsSet> image_cursors_set_weak_ptr = nullptr;
+
+   private:
+    DISALLOW_COPY_AND_ASSIGN(InProcessConfig);
+  };
+
+  // |config| should be null when UI Service runs in it's own separate process,
+  // as opposed to inside the Window Manager's process.
+  explicit Service(const InProcessConfig* config = nullptr);
   ~Service() override;
 
  private:
@@ -74,6 +96,8 @@ class Service : public service_manager::Service,
 
   using UserIdToUserState = std::map<ws::UserId, std::unique_ptr<UserState>>;
 
+  bool is_in_process() const { return is_in_process_; }
+
   // Attempts to initialize the resource bundle. Returns true if successful,
   // otherwise false if resources cannot be loaded.
   bool InitializeResources(service_manager::Connector* connector);
@@ -99,6 +123,7 @@ class Service : public service_manager::Service,
   bool IsTestConfig() const override;
   void OnWillCreateTreeForWindowManager(
       bool automatically_create_display_roots) override;
+  ws::ThreadedImageCursorsFactory* GetThreadedImageCursorsFactory() override;
 
   void BindAccessibilityManagerRequest(
       const service_manager::BindSourceInfo& source_info,
@@ -150,7 +175,7 @@ class Service : public service_manager::Service,
       mojom::WindowServerTestRequest request);
 
   std::unique_ptr<ws::WindowServer> window_server_;
-  std::unique_ptr<ui::PlatformEventSource> event_source_;
+  std::unique_ptr<PlatformEventSource> event_source_;
   using PendingRequests = std::vector<std::unique_ptr<PendingRequest>>;
   PendingRequests pending_requests_;
 
@@ -160,6 +185,13 @@ class Service : public service_manager::Service,
   // and must outlive |registry_|.
   InputDeviceServer input_device_server_;
 
+  // True if the UI Service runs inside WM's process, false if it runs inside
+  // its own process.
+  const bool is_in_process_;
+
+  std::unique_ptr<ws::ThreadedImageCursorsFactory>
+      threaded_image_cursors_factory_;
+
   bool test_config_;
 #if defined(USE_OZONE)
   std::unique_ptr<gfx::ClientNativePixmapFactory> client_native_pixmap_factory_;