Always reset touch action at the beginning of a new gesture sequence

content/browser/renderer_host/input/input_router_impl.cc

 // Copyright 2013 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.
 
 #include "content/browser/renderer_host/input/input_router_impl.h"
 
 #include "base/auto_reset.h"
 #include "base/command_line.h"
 #include "base/metrics/histogram.h"
 #include "base/strings/string_number_conversions.h"
@@ skipping 241 matching lines @@
     if (controller)
       controller->DiscardingGestureEvent(gesture_event.event);
     return;
   }
 
   FilterAndSendWebInputEvent(gesture_event.event, gesture_event.latency, false);
 }
 
 void InputRouterImpl::SendTouchEvent(
     const TouchEventWithLatencyInfo& touch_event) {
+  if (WebInputEventTraits::IsNewTouchSequence(touch_event.event))

[Rick Byers, 2014/02/18 22:01:15]

Doesn't this need to go in SendTouchEventImmediately instead?  If the renderer
is busy and we're queuing up multiple touch sequences in the TEQ, then we may
still be processing gestures associated with the _previous_ sequence.

Can you look into adding a unit test for this sort of timing issue?  I think
it's probably the most subtle/brittle aspect of touch-action behavior.  Perhaps
an input-router unit test with a mock TEQ but real TouchActionFilter?

[tdresser, 2014/02/20 18:37:56]

Done.

+    touch_action_filter_.StartNewTouchActionSequence();
   touch_event_queue_->QueueEvent(touch_event);
 }
 
 // Forwards MouseEvent without passing it through
 // TouchpadTapSuppressionController.
 void InputRouterImpl::SendMouseEventImmediately(
     const MouseEventWithLatencyInfo& mouse_event) {
   // Avoid spamming the renderer with mouse move events.  It is important
   // to note that WM_MOUSEMOVE events are anyways synthetic, but since our
   // thread is able to rapidly consume WM_MOUSEMOVE events, we may get way
@@ skipping 491 matching lines @@
       break;
   }
 }
 
 bool InputRouterImpl::IsInOverscrollGesture() const {
   OverscrollController* controller = client_->GetOverscrollController();
   return controller && controller->overscroll_mode() != OVERSCROLL_NONE;
 }
 
 }  // namespace content