Add use counter when touch-action isn't used when preventDefault'd.

third_party/WebKit/Source/core/input/TouchEventManager.cpp

Index: third_party/WebKit/Source/core/input/TouchEventManager.cpp
diff --git a/third_party/WebKit/Source/core/input/TouchEventManager.cpp b/third_party/WebKit/Source/core/input/TouchEventManager.cpp
index 8cbaab593786745703e2db82a91ca6fa5f5c0b07..c6153a059c300b7b7546322d862906bf9025fa04 100644
--- a/third_party/WebKit/Source/core/input/TouchEventManager.cpp
+++ b/third_party/WebKit/Source/core/input/TouchEventManager.cpp
@@ -97,6 +97,7 @@ void TouchEventManager::clear() {
   m_touchPressed = false;
   m_touchScrollStarted = false;
   m_currentEvent = PlatformEvent::NoType;
+  m_currentTouchAction = TouchActionAuto;
 }
 
 DEFINE_TRACE(TouchEventManager) {
@@ -172,6 +173,7 @@ WebInputEventResult TouchEventManager::dispatchTouchEvents(
   if (allTouchesReleased) {
     m_touchSequenceDocument.clear();
     m_touchSequenceUserGestureToken.clear();
+    m_currentTouchAction = TouchActionAuto;
   }
 
   WebInputEventResult eventResult = WebInputEventResult::NotHandled;
@@ -187,13 +189,14 @@ WebInputEventResult TouchEventManager::dispatchTouchEvents(
         static_cast<PlatformTouchPoint::TouchState>(state)));
     for (const auto& eventTarget : changedTouches[state].m_targets) {
       EventTarget* touchEventTarget = eventTarget;
-      TouchEvent* touchEvent = TouchEvent::create(
-          touches, touchesByTarget.get(touchEventTarget),
-          changedTouches[state].m_touches.get(), eventName,
-          touchEventTarget->toNode()->document().domWindow(),
-          event.getModifiers(), event.cancelable(),
-          event.causesScrollingIfUncanceled(),
-          event.touchStartOrFirstTouchMove(), event.timestamp());
+      TouchEvent* touchEvent =
+          TouchEvent::create(touches, touchesByTarget.get(touchEventTarget),
+                             changedTouches[state].m_touches.get(), eventName,
+                             touchEventTarget->toNode()->document().domWindow(),
+                             event.getModifiers(), event.cancelable(),
+                             event.causesScrollingIfUncanceled(),
+                             event.touchStartOrFirstTouchMove(),
+                             event.timestamp(), m_currentTouchAction);
 
       DispatchEventResult domDispatchResult =
           touchEventTarget->dispatchEvent(touchEvent);
@@ -343,6 +346,7 @@ void TouchEventManager::updateTargetAndRegionMapsForTouchStarts(
           TouchActionUtil::computeEffectiveTouchAction(*touchInfo.touchNode);
       if (effectiveTouchAction != TouchActionAuto)
         m_frame->page()->chromeClient().setTouchAction(effectiveTouchAction);
+      m_currentTouchAction = effectiveTouchAction;

[Rick Byers, 2016/11/07 17:01:09]

This isn't sufficient for multi-finger gestures.  IIRC the browser computes the
intersection of the touch actions for each active finger.  If I'm not forgetting
some subtlty then I think you can trivially repeat that logic here (ignoring
OOPIF anyway).

[dtapuska, 2016/11/07 18:51:40]

Done.

     }
   }
 }