exo: Implement v6 of touch protocol including shape and frame event

components/exo/touch.cc

Index: components/exo/touch.cc
diff --git a/components/exo/touch.cc b/components/exo/touch.cc
index f0db59594419a36274fe3312914d6f254223ff90..a055d45415381a1fe298f74a79fa38879af8b413 100644
--- a/components/exo/touch.cc
+++ b/components/exo/touch.cc
@@ -118,8 +118,17 @@ void Touch::OnTouchEvent(ui::TouchEvent* event) {
     } break;
     default:
       NOTREACHED();
-      break;
+      return;
   }
+  if (event->type() == ui::ET_TOUCH_PRESSED ||
+      event->type() == ui::ET_TOUCH_MOVED) {
+    delegate_->OnTouchShape(event->touch_id(),

[reveman, 2016/12/08 01:40:45]

Can you move this up into the switch cases above instead so we only send it if
the touch id is valid? That way we also avoid branching twice.

+                            event->pointer_details().radius_x,
+                            event->pointer_details().radius_y);
+  }
+  // todo(denniskempin): Extend ui::TouchEvent to signal end of sequence of

[reveman, 2016/12/08 01:40:45]

s/todo/TODO/

+  // touch events to send TouchFrame once after all touches have been updated.
+  delegate_->OnTouchFrame();

[reveman, 2016/12/08 01:40:45]

Move this up into the switch cases as well to avoid sending if touch_id is not
valid.

 }
 
 ////////////////////////////////////////////////////////////////////////////////