Adding drawable to CRD andorid and iOS gl rendering pipeline.

remoting/client/display/gl_cursor.h

 // Copyright 2016 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.
 
 #ifndef REMOTING_CLIENT_DISPLAY_GL_CURSOR_H_
 #define REMOTING_CLIENT_DISPLAY_GL_CURSOR_H_
 
 #include <array>
 #include <cstdint>
 #include <memory>
 
 #include "base/macros.h"
+#include "base/memory/weak_ptr.h"
+#include "base/threading/thread_checker.h"
+#include "remoting/client/display/drawable.h"
 
 namespace remoting {
 
 namespace protocol {
 class CursorShapeInfo;
 }  // namespace protocol
 
-class GlCanvas;
+class Canvas;
 class GlRenderLayer;
 
 // This class draws the cursor on the canvas.
-class GlCursor {
+class GlCursor : public Drawable {
  public:
   GlCursor();
-  ~GlCursor();
+  ~GlCursor() override;
 
   void SetCursorShape(const protocol::CursorShapeInfo& cursor_shape);
 
   // Sets the cursor hotspot positions. Does nothing if the cursor shape or the
   // canvas size has not been set.
   void SetCursorPosition(float x, float y);
 
   // Draw() will do nothing if cursor is not visible.
   void SetCursorVisible(bool visible);
 
-  // Sets the canvas on which the cursor will be drawn. Resumes the current
-  // state of the cursor to the context of the new canvas.
-  // If |canvas| is nullptr, nothing will happen when calling Draw().
-  void SetCanvas(GlCanvas* canvas);
-
-  void Draw();
+  // Drawable implementation.
+  void SetCanvas(base::WeakPtr<Canvas> canvas) override;
+  bool Draw() override;
+  int GetZIndex() override;
+  base::WeakPtr<Drawable> GetWeakPtr() override;
 
  private:
   void SetCurrentCursorShape(bool size_changed);
 
   bool visible_ = true;
 
   std::unique_ptr<GlRenderLayer> layer_;
 
   std::unique_ptr<uint8_t[]> current_cursor_data_;
   int current_cursor_data_size_ = 0;
   int current_cursor_width_ = 0;
   int current_cursor_height_ = 0;
   int current_cursor_hotspot_x_ = 0;
   int current_cursor_hotspot_y_ = 0;
 
   float cursor_x_ = 0;
   float cursor_y_ = 0;
 
+  base::ThreadChecker thread_checker_;
+  base::WeakPtrFactory<Drawable> weak_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(GlCursor);
 };
 
 }  // namespace remoting
 #endif  // REMOTING_CLIENT_DISPLAY_GL_CURSOR_H_