[CRD iOS] Ignore touch event when the touch point is out of the canvas in direct input mode

remoting/client/ui/trackpad_input_strategy.h

 // Copyright 2017 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_UI_TRACKPAD_INPUT_STRATEGY_H_
 #define REMOTING_CLIENT_UI_TRACKPAD_INPUT_STRATEGY_H_
 
 #include "remoting/client/ui/input_strategy.h"
 
 namespace remoting {
 
 // This strategy simulate the trackpad's behavior. It keeps a visible cursor
 // with positions independent of the location of the touch events.
 class TrackpadInputStrategy : public InputStrategy {
  public:
   TrackpadInputStrategy(const DesktopViewport& viewport);
   ~TrackpadInputStrategy() override;
 
   // InputStrategy overrides.
   void HandleZoom(const ViewMatrix::Point& pivot,
                   float scale,
                   DesktopViewport* viewport) override;
 
   bool HandlePan(const ViewMatrix::Vector2D& translation,
                  Gesture simultaneous_gesture,
                  DesktopViewport* viewport) override;
 
-  void TrackTouchInput(const ViewMatrix::Point& touch_point,
+  bool TrackTouchInput(const ViewMatrix::Point& touch_point,
                        const DesktopViewport& viewport) override;
 
   ViewMatrix::Point GetCursorPosition() const override;
 
   ViewMatrix::Vector2D MapScreenVectorToDesktop(
       const ViewMatrix::Vector2D& delta,
       const DesktopViewport& viewport) const override;
 
   float GetFeedbackRadius(InputFeedbackType type) const override;
 
   bool IsCursorVisible() const override;
 
  private:
   ViewMatrix::Point cursor_position_;
 
   // TrackpadInputStrategy is neither copyable nor movable.
   TrackpadInputStrategy(const TrackpadInputStrategy&) = delete;
   TrackpadInputStrategy& operator=(const TrackpadInputStrategy&) = delete;
 };
 
 }  // namespace remoting
 #endif  // REMOTING_CLIENT_UI_TRACKPAD_INPUT_STRATEGY_H_