Add touch events to the protocol, the stub layer, and to the client plugin.

- Add TouchEvent and TouchEventPoint messages to the input event protocol.
- Extend the InputStub interface with an InjectTouchEvent() method.
- Update InputEventTracker to track touch points, and to cancel them
  when ReleaseAll() is called.
- Implement touch handling in the client plugin, but off by default.
  The web-app may choose to enable touch handling if desired.
- Add a TouchInputScaler that scales and clamps touch points, similarly to
  the MouseInputFilter, for use by both client and host.

BUG=314515

Review URL: https://codereview.chromium.org/799233004

Cr-Commit-Position: refs/heads/master@{#318284}

1 files changed, 1 insertions, 0 deletions

diff --git a/remoting/protocol/client_event_dispatcher.h b/remoting/protocol/client_event_dispatcher.h
index d0140c5..22b1588 100644
--- a/remoting/protocol/client_event_dispatcher.h
+++ b/remoting/protocol/client_event_dispatcher.h
@@ -23,6 +23,7 @@ class ClientEventDispatcher : public ChannelDispatcherBase, public InputStub {
   void InjectKeyEvent(const KeyEvent& event) override;
   void InjectTextEvent(const TextEvent& event) override;
   void InjectMouseEvent(const MouseEvent& event) override;
+  void InjectTouchEvent(const TouchEvent& event) override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(ClientEventDispatcher);