[Remoting Android] Separate the display core from JniGlDisplayHandler

This CL separates the core that lives entirely on the display thread from
JniGlDisplayHandler so that the thread model can be clearer.

BUG=646116

Review-Url: https://codereview.chromium.org/2389463002
Cr-Commit-Position: refs/heads/master@{#422988}

remoting/client/jni/jni_client.cc

@@ -48,8 +48,10 @@ void JniClient::ConnectToHost(const std::string& username,
                               const std::string& capabilities,
                               const std::string& flags) {
   DCHECK(runtime_->ui_task_runner()->BelongsToCurrentThread());
+  DCHECK(!display_handler_);
   DCHECK(!session_);
   DCHECK(!secret_fetcher_);
+  display_handler_.reset(new JniGlDisplayHandler(runtime_, java_client_));
   secret_fetcher_.reset(new JniPairingSecretFetcher(runtime_, GetWeakPtr(),
                                                     host_id));
   session_.reset(new ChromotingJniInstance(
@@ -72,11 +74,7 @@ void JniClient::DisconnectFromHost() {
     runtime_->network_task_runner()->DeleteSoon(FROM_HERE,
                                                 secret_fetcher_.release());
   }
-  if (display_handler_) {
-    display_handler_->Invalidate();
-    runtime_->display_task_runner()->DeleteSoon(FROM_HERE,
-                                                display_handler_.release());
-  }
+  display_handler_.reset();
 }
 
 void JniClient::OnConnectionState(protocol::ConnectionToHost::State state,
@@ -161,8 +159,6 @@ void JniClient::Connect(
     const base::android::JavaParamRef<jstring>& pairSecret,
     const base::android::JavaParamRef<jstring>& capabilities,
     const base::android::JavaParamRef<jstring>& flags) {
-  display_handler_.reset(new JniGlDisplayHandler(runtime_));
-  display_handler_->Initialize(java_client_);
   ConnectToHost(ConvertJavaStringToUTF8(env, username),
                 ConvertJavaStringToUTF8(env, authToken),
                 ConvertJavaStringToUTF8(env, hostJid),

remoting/client/jni/jni_gl_display_handler.h

@@ -13,6 +13,7 @@
 #include "base/memory/weak_ptr.h"
 #include "remoting/client/gl_renderer.h"
 #include "remoting/client/gl_renderer_delegate.h"
+#include "remoting/client/queued_task_poster.h"
 #include "remoting/protocol/cursor_shape_stub.h"
 
 namespace remoting {
@@ -24,28 +25,15 @@ class VideoRenderer;
 class ChromotingJniRuntime;
 class DualBufferFrameConsumer;
 class EglThreadContext;
-class QueuedTaskPoster;
 
 // Handles OpenGL display operations. Draws desktop and cursor on the OpenGL
-// surface.
-// JNI functions should all be called on the UI thread. user must call
-// Initialize() after the handler is constructed and Invalidate() before the
-// handler is destructed. The destructor must be called on the display thread.
-// Please see GlDisplay.java for documentations.
-// TODO(yuweih): Separate display thread logic into a core class.
-class JniGlDisplayHandler : public protocol::CursorShapeStub,
-                            public GlRendererDelegate {
+// surface. The handler should be used and destroyed on the UI thread. It also
+// has a core that works on the display thread.
+class JniGlDisplayHandler {
  public:
-  JniGlDisplayHandler(ChromotingJniRuntime* runtime);
-
-  // Destructor must be called on the display thread.
-  ~JniGlDisplayHandler() override;
-
-  // Must be called exactly once on the UI thread before using the handler.
-  void Initialize(const base::android::JavaRef<jobject>& java_client);
-
-  // Must be called on the UI thread before calling the destructor.
-  void Invalidate();
+  JniGlDisplayHandler(ChromotingJniRuntime* runtime,
+                      const base::android::JavaRef<jobject>& java_client);
+  ~JniGlDisplayHandler();
 
   std::unique_ptr<protocol::CursorShapeStub> CreateCursorShapeStub();
   std::unique_ptr<protocol::VideoRenderer> CreateVideoRenderer();
@@ -91,47 +79,21 @@ class JniGlDisplayHandler : public protocol::CursorShapeStub,
       float diameter);
 
  private:
-  // Queues a task. All queued tasks will be posted to the display thread after
-  // the current task is finished.
-  // Do nothing if |ui_task_poster_| has already been released.
-  void PostSequentialTaskOnDisplayThread(const base::Closure& task);
-
-  // GlRendererDelegate interface.
-  bool CanRenderFrame() override;
-  void OnFrameRendered() override;
-  void OnSizeChanged(int width, int height) override;
-
-  // CursorShapeStub interface.
-  void SetCursorShape(const protocol::CursorShapeInfo& cursor_shape) override;
-
-  static void NotifyRenderDoneOnUiThread(
-      base::android::ScopedJavaGlobalRef<jobject> java_display);
+  class Core;
 
-  void SurfaceCreatedOnDisplayThread(
-      base::android::ScopedJavaGlobalRef<jobject> surface);
-
-  void SurfaceDestroyedOnDisplayThread();
-
-  static void ChangeCanvasSizeOnUiThread(
-      base::android::ScopedJavaGlobalRef<jobject> java_display,
-      int width,
-      int height);
+  // Callbacks from the core.
+  void OnRenderDone();
+  void OnCanvasSizeChanged(int width, int height);
 
   ChromotingJniRuntime* runtime_;
 
-  base::android::ScopedJavaGlobalRef<jobject> java_display_;
-
-  std::unique_ptr<EglThreadContext> egl_context_;
-
-  base::WeakPtr<DualBufferFrameConsumer> frame_consumer_;
+  QueuedTaskPoster ui_task_poster_;
 
-  // |renderer_| must be deleted earlier than |egl_context_|.
-  GlRenderer renderer_;
+  std::unique_ptr<Core> core_;
 
-  std::unique_ptr<QueuedTaskPoster> ui_task_poster_;
+  base::android::ScopedJavaGlobalRef<jobject> java_display_;
 
-  // Used on display thread.
-  base::WeakPtr<JniGlDisplayHandler> weak_ptr_;
+  // Used on UI thread.
   base::WeakPtrFactory<JniGlDisplayHandler> weak_factory_;
   DISALLOW_COPY_AND_ASSIGN(JniGlDisplayHandler);
 };