Use mojo for cursor control in ozone drm

ui/ozone/platform/drm/ozone_platform_gbm.cc

Index: ui/ozone/platform/drm/ozone_platform_gbm.cc
diff --git a/ui/ozone/platform/drm/ozone_platform_gbm.cc b/ui/ozone/platform/drm/ozone_platform_gbm.cc
index 657aad01e307804ea092d52b2c12dec618691ee1..fb276c4b70a19eec671da81a4bd8b76b6a12290f 100644
--- a/ui/ozone/platform/drm/ozone_platform_gbm.cc
+++ b/ui/ozone/platform/drm/ozone_platform_gbm.cc
@@ -17,11 +17,14 @@
 #include "base/command_line.h"
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
+#include "services/shell/public/cpp/connection.h"
+#include "services/shell/public/cpp/interface_factory.h"
 #include "ui/base/cursor/ozone/bitmap_cursor_factory_ozone.h"
 #include "ui/events/ozone/device/device_manager.h"
 #include "ui/events/ozone/evdev/event_factory_evdev.h"
 #include "ui/events/ozone/layout/keyboard_layout_engine_manager.h"
 #include "ui/ozone/platform/drm/common/drm_util.h"
+#include "ui/ozone/platform/drm/cursor_proxy_mojo.h"
 #include "ui/ozone/platform/drm/gpu/drm_device_generator.h"
 #include "ui/ozone/platform/drm/gpu/drm_device_manager.h"
 #include "ui/ozone/platform/drm/gpu/drm_gpu_display_manager.h"
@@ -77,18 +80,11 @@ class GlApiLoader {
   DISALLOW_COPY_AND_ASSIGN(GlApiLoader);
 };
 
-// Returns true if we should operate in Mus mode.
-// TODO(rjkroege): Create an explicit "single process ozone mode" that can be
-// used for tests after mus+ash team finishes splitting mus.
-bool RunningInsideMus() {
-  bool has_channel_handle = base::CommandLine::ForCurrentProcess()->HasSwitch(
-      "mojo-platform-channel-handle");
-  return has_channel_handle;
-}
-
-class OzonePlatformGbm : public OzonePlatform {
+class OzonePlatformGbm
+    : public OzonePlatform,
+      public shell::InterfaceFactory<ozone::mojom::DeviceCursor> {
  public:
-  OzonePlatformGbm() {}
+  OzonePlatformGbm() : using_mojo_(false), single_process_(false) {}
   ~OzonePlatformGbm() override {}
 
   // OzonePlatform:
@@ -113,11 +109,20 @@ class OzonePlatformGbm : public OzonePlatform {
   std::unique_ptr<SystemInputInjector> CreateSystemInputInjector() override {
     return event_factory_ozone_->CreateSystemInputInjector();
   }
+  void AddInterfaces(shell::Connection* connection) override {
+    connection->AddInterface<ozone::mojom::DeviceCursor>(this);
+  }
+  // shell::InterfaceFactory<mojom::ozone::Cursor> implementation.
+  void Create(const shell::Identity& remote_identity,
+              ozone::mojom::DeviceCursorRequest request) override {
+    DCHECK(drm_thread_);
+    drm_thread_->AddBinding(std::move(request));
+  }
   std::unique_ptr<PlatformWindow> CreatePlatformWindow(
       PlatformWindowDelegate* delegate,
       const gfx::Rect& bounds) override {
     GpuThreadAdapter* adapter = gpu_platform_support_host_.get();
-    if (RunningInsideMus()) {
+    if (using_mojo_ || single_process_) {
       DCHECK(drm_thread_) << "drm_thread_ should exist (and be running) here.";
       adapter = mus_thread_proxy_.get();
     }
@@ -134,6 +139,24 @@ class OzonePlatformGbm : public OzonePlatform {
         new DrmNativeDisplayDelegate(display_manager_.get()));
   }
   void InitializeUI() override {
+    InitParams default_params;
+    InitializeUI(default_params);
+  }
+  void InitializeUI(const InitParams& args) override {
+    // Ozone drm can operate in three modes configured at runtime:
+    //   1. legacy mode where browser and gpu components communicate
+    //      via param traits IPC.
+    //   2. single-process mode where browser and gpu components
+    //      communicate via PostTask.
+    //   3. mojo mode where browser and gpu components communicate
+    //      via mojo IPC.
+    // Currently, mojo mode uses mojo in a single process but this is
+    // an interim implementation detail that will be eliminated in a
+    // future CL.
+    single_process_ = args.single_process;
+    using_mojo_ = args.connector != nullptr;
+    DCHECK(!(using_mojo_ && single_process_));
+
     device_manager_ = CreateDeviceManager();
     window_manager_.reset(new DrmWindowHostManager());
     cursor_.reset(new DrmCursor(window_manager_.get()));
@@ -144,16 +167,27 @@ class OzonePlatformGbm : public OzonePlatform {
     KeyboardLayoutEngineManager::SetKeyboardLayoutEngine(
         base::WrapUnique(new StubKeyboardLayoutEngine()));
 #endif
+
     event_factory_ozone_.reset(new EventFactoryEvdev(
         cursor_.get(), device_manager_.get(),
         KeyboardLayoutEngineManager::GetKeyboardLayoutEngine()));
 
     GpuThreadAdapter* adapter;
-    if (RunningInsideMus()) {
+
+    // TODO(rjkroege): Once mus is split, only do this for single_process.
+    if (single_process_ || using_mojo_)
       gl_api_loader_.reset(new GlApiLoader());
+
+    if (using_mojo_) {
+      DCHECK(args.connector);
+      mus_thread_proxy_.reset(new MusThreadProxy());
+      adapter = mus_thread_proxy_.get();
+      cursor_->SetDrmCursorProxy(new CursorProxyMojo(args.connector));
+    } else if (single_process_) {
       mus_thread_proxy_.reset(new MusThreadProxy());
       adapter = mus_thread_proxy_.get();
-      cursor_->SetDrmCursorProxy(mus_thread_proxy_.get());
+      cursor_->SetDrmCursorProxy(
+          new CursorProxyThread(mus_thread_proxy_.get()));
     } else {
       gpu_platform_support_host_.reset(
           new DrmGpuPlatformSupportHost(cursor_.get()));
@@ -167,16 +201,24 @@ class OzonePlatformGbm : public OzonePlatform {
     overlay_manager_.reset(
         new DrmOverlayManager(adapter, window_manager_.get()));
 
-    if (RunningInsideMus()) {
+    if (using_mojo_ || single_process_) {
       mus_thread_proxy_->ProvideManagers(display_manager_.get(),
                                          overlay_manager_.get());
     }
   }
-
   void InitializeGPU() override {
+    InitParams default_params;
+    InitializeGPU(default_params);
+  }
+  void InitializeGPU(const InitParams& args) override {
+    // TODO(rjkroege): services/ui should initalize this with a connector.
+    // However, in-progress refactorings in services/ui make it difficult to
+    // require this at present. Set using_mojo_ like below once this is
+    // complete.
+    // using_mojo_ = args.connector != nullptr;
+
     InterThreadMessagingProxy* itmp;
-    if (RunningInsideMus()) {
-      DCHECK(mus_thread_proxy_);
+    if (using_mojo_ || single_process_) {
       itmp = mus_thread_proxy_.get();
     } else {
       gl_api_loader_.reset(new GlApiLoader());
@@ -192,13 +234,17 @@ class OzonePlatformGbm : public OzonePlatform {
     drm_thread_->BindThreadIntoMessagingProxy(itmp);
 
     surface_factory_.reset(new GbmSurfaceFactory(drm_thread_.get()));
-    if (RunningInsideMus()) {
+    if (using_mojo_ || single_process_) {
       mus_thread_proxy_->StartDrmThread();
     }
   }
 
  private:
+  bool using_mojo_;
+  bool single_process_;
+
   // Objects in the GPU process.
+  // TODO(rjk): rename drm_thread_ to drm_thread_proxy_;
   std::unique_ptr<DrmThreadProxy> drm_thread_;
   std::unique_ptr<GlApiLoader> gl_api_loader_;
   std::unique_ptr<GbmSurfaceFactory> surface_factory_;