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

remoting/client/ui/direct_input_strategy.cc

 // 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.
 
 #include "remoting/client/ui/direct_input_strategy.h"
 #include "remoting/client/ui/desktop_viewport.h"
 
 namespace remoting {
 
 namespace {
@@ skipping 23 matching lines @@
     ViewMatrix::Vector2D viewport_movement =
         viewport->GetTransformation().Invert().MapVector(translation);
     viewport->MoveViewport(viewport_movement.x, viewport_movement.y);
     return false;
   }
 
   viewport->MoveDesktop(translation.x, translation.y);
   return false;
 }
 
-void DirectInputStrategy::TrackTouchInput(const ViewMatrix::Point& touch_point,
+bool DirectInputStrategy::TrackTouchInput(const ViewMatrix::Point& touch_point,
                                           const DesktopViewport& viewport) {
-  cursor_position_ =
+  ViewMatrix::Point new_position =
       viewport.GetTransformation().Invert().MapPoint(touch_point);
+  if (!viewport.IsPointWithinDesktopBounds(new_position)) {
+    return false;
+  }
+  cursor_position_ = new_position;
+  return true;
 }
 
 ViewMatrix::Point DirectInputStrategy::GetCursorPosition() const {
   return cursor_position_;
 }
 
 ViewMatrix::Vector2D DirectInputStrategy::MapScreenVectorToDesktop(
     const ViewMatrix::Vector2D& delta,
     const DesktopViewport& viewport) const {
   return viewport.GetTransformation().Invert().MapVector(delta);
 }
 
 float DirectInputStrategy::GetFeedbackRadius(InputFeedbackType type) const {
   switch (type) {
     case InputFeedbackType::TAP_FEEDBACK:
       return kTapFeedbackRadius;
     case InputFeedbackType::DRAG_FEEDBACK:
       return kDragFeedbackRadius;
   }
   NOTREACHED();
   return 0.f;
 }
 
 bool DirectInputStrategy::IsCursorVisible() const {
   return false;
 }
 
 }  // namespace remoting