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

remoting/client/plugin/touch_input_scaler.h

Index: remoting/client/plugin/touch_input_scaler.h
diff --git a/remoting/client/plugin/touch_input_scaler.h b/remoting/client/plugin/touch_input_scaler.h
new file mode 100644
index 0000000000000000000000000000000000000000..51617918c7bd8fbec8631992adbaa17736ffe65d
--- /dev/null
+++ b/remoting/client/plugin/touch_input_scaler.h
@@ -0,0 +1,48 @@
+// Copyright 2015 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_PLUGIN_TOUCH_INPUT_SCALER_H_
+#define REMOTING_CLIENT_PLUGIN_TOUCH_INPUT_SCALER_H_
+
+#include "remoting/protocol/input_filter.h"
+#include "third_party/webrtc/modules/desktop_capture/desktop_geometry.h"
+
+namespace remoting {
+
+namespace protocol {
+class TouchEvent;
+}  // namespace protocol
+
+// Scales the touch input coordinates to host coordinates and clamps so
+// that the values do not go outside the remote desktop.
+// Also resizes the touch size.
+class TouchInputScaler : public protocol::InputFilter {
+ public:
+  TouchInputScaler() = default;
+  explicit TouchInputScaler(InputStub* input_stub);
+  ~TouchInputScaler() override;
+
+  // Set input and output desktop sizes.
+  void set_input_size(const webrtc::DesktopSize& size) {
+    input_size_.set(size.width() - 1, size.height() - 1);
+  }
+  void set_output_size(const webrtc::DesktopSize& size) {
+    output_size_.set(size.width() - 1, size.height() - 1);
+  }
+
+  // protocol::InputStub interface.
+  void InjectTouchEvent(const protocol::TouchEvent& event) override;
+
+ private:
+  // Sizes for scaling and clamping coordinates and sizes.
+  // These hold the max-X,Y coordinates and not the actual width and height.
+  webrtc::DesktopSize input_size_;
+  webrtc::DesktopSize output_size_;
+
+  DISALLOW_COPY_AND_ASSIGN(TouchInputScaler);
+};
+
+}  // namespace remoting
+
+#endif  // REMOTING_CLIENT_PLUGIN_TOUCH_INPUT_SCALER_H_