Expose Gamepad API instance for Cardboard button

device/vr/android/gvr/gvr_gamepad_data_provider.h

Index: device/vr/android/gvr/gvr_gamepad_data_provider.h
diff --git a/device/vr/android/gvr/gvr_gamepad_data_provider.h b/device/vr/android/gvr/gvr_gamepad_data_provider.h
index fcfcf68b94de7da0f70a65f4a15b72bac9c7d340..ca1172189f5a61a85c394619116e2d12469c7916 100644
--- a/device/vr/android/gvr/gvr_gamepad_data_provider.h
+++ b/device/vr/android/gvr/gvr_gamepad_data_provider.h
@@ -15,13 +15,14 @@ class GvrGamepadDataFetcher;
 // by vr_shell's VrController and consumed by GvrGamepadDataFetcher.
 struct GvrGamepadData {
   int64_t timestamp;
-  gfx::Vector2dF touch_pos;
+  gfx::Vector2dF touch_pos;  // Controller touch position.
   vr::Quatf orientation;
   gfx::Vector3dF accel;
   gfx::Vector3dF gyro;
-  bool is_touching;
+  bool is_controller_touching;
   bool controller_button_pressed;
   bool right_handed;
+  bool is_screen_touching;  // For cardboard, only the screen touch matters
 };
 
 // This class exposes GVR controller data to the gamepad API. Data is