Articulate the cancel behavior in the WebTouchEvent.

content/browser/renderer_host/input/input_router_impl.cc

Index: content/browser/renderer_host/input/input_router_impl.cc
diff --git a/content/browser/renderer_host/input/input_router_impl.cc b/content/browser/renderer_host/input/input_router_impl.cc
index ed58284be37f3f611fd722c3e1d611334bbf12aa..0de81d21a5d5ec222a6acf9af9c3dd1c529b5420 100644
--- a/content/browser/renderer_host/input/input_router_impl.cc
+++ b/content/browser/renderer_host/input/input_router_impl.cc
@@ -368,10 +368,7 @@ void InputRouterImpl::OfferToHandlers(const WebInputEvent& input_event,
   if (OfferToClient(input_event, latency_info))
     return;
 
-  // Touch events should always indicate in the event whether they are
-  // cancelable (respect ACK disposition) or not except touchmove.
   bool should_block = WebInputEventTraits::ShouldBlockEventStream(input_event);
-
   OfferToRenderer(input_event, latency_info,
                   should_block
                       ? InputEventDispatchType::DISPATCH_TYPE_BLOCKING