Add suppresion of slop region touches in browser

content/browser/renderer_host/input/passthrough_touch_event_queue.h

Index: content/browser/renderer_host/input/passthrough_touch_event_queue.h
diff --git a/content/browser/renderer_host/input/passthrough_touch_event_queue.h b/content/browser/renderer_host/input/passthrough_touch_event_queue.h
index cae55abf2450fde3ba8154db656c4273a8f3febe..d38ee425b19094b6604749119b49c6367701a8f0 100644
--- a/content/browser/renderer_host/input/passthrough_touch_event_queue.h
+++ b/content/browser/renderer_host/input/passthrough_touch_event_queue.h
@@ -12,6 +12,7 @@
 namespace content {
 
 class TouchTimeoutHandler;
+class TouchMoveSlopSuppressor;
 
 // A queue that processes a touch-event and forwards it on to the
 // renderer process immediately. This class assumes that queueing will
@@ -115,6 +116,10 @@ class CONTENT_EXPORT PassthroughTouchEventQueue : public TouchEventQueue {
   // cancelled after a touch timeout.
   bool drop_remaining_touches_in_sequence_;
 
+  // Suppresses TouchMove's within a slop region when a sequence has not yet
+  // been preventDefaulted.
+  std::unique_ptr<TouchMoveSlopSuppressor> touchmove_slop_suppressor_;
+
   // Optional handler for timed-out touch event acks.
   std::unique_ptr<TouchTimeoutHandler> timeout_handler_;