Non passive touch end or touch cancel listeners should not block scroll.

third_party/WebKit/Source/web/ChromeClientImpl.cpp

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
@@ skipping 893 matching lines @@
 bool ChromeClientImpl::shouldOpenModalDialogDuringPageDismissal(const DialogType& dialogType, const String& dialogMessage, Document::PageDismissalType dismissalType) const
 {
     String message = String("Blocked ") + dialogTypeToString(dialogType) + "('" + dialogMessage + "') during " + dismissalTypeToString(dismissalType) + ".";
     m_webView->mainFrame()->addMessageToConsole(WebConsoleMessage(WebConsoleMessage::LevelError, message));
 
     return false;
 }
 
 void ChromeClientImpl::setEventListenerProperties(WebEventListenerClass eventClass, WebEventListenerProperties properties)
 {
-    if (eventClass == WebEventListenerClass::Touch)
-        m_webView->hasTouchEventHandlers(properties != WebEventListenerProperties::Nothing);
-
-    if (WebLayerTreeView* treeView = m_webView->layerTreeView())
+    if (WebLayerTreeView* treeView = m_webView->layerTreeView()) {
         treeView->setEventListenerProperties(eventClass, properties);
+        if (eventClass == WebEventListenerClass::TouchStartOrMove) {
+            m_webView->hasTouchEventHandlers(properties != WebEventListenerProperties::Nothing || eventListenerProperties(WebEventListenerClass::TouchEndOrCancel) != WebEventListenerProperties::Nothing);
+        } else if (eventClass == WebEventListenerClass::TouchEndOrCancel) {
+            m_webView->hasTouchEventHandlers(properties != WebEventListenerProperties::Nothing || eventListenerProperties(WebEventListenerClass::TouchStartOrMove) != WebEventListenerProperties::Nothing);
+        }
+    } else {
+        m_webView->hasTouchEventHandlers(true);
+    }
 }
 
 WebEventListenerProperties ChromeClientImpl::eventListenerProperties(WebEventListenerClass eventClass) const
 {
     if (WebLayerTreeView* treeView = m_webView->layerTreeView())
         return treeView->eventListenerProperties(eventClass);
     return WebEventListenerProperties::Nothing;
 }
 
-void ChromeClientImpl::setHaveScrollEventHandlers(bool hasEventHandlers)
+void ChromeClientImpl::setHasScrollEventHandlers(bool hasEventHandlers)
 {
     if (WebLayerTreeView* treeView = m_webView->layerTreeView())
         treeView->setHaveScrollEventHandlers(hasEventHandlers);
 }
 
-bool ChromeClientImpl::haveScrollEventHandlers() const
+bool ChromeClientImpl::hasScrollEventHandlers() const
 {
     if (WebLayerTreeView* treeView = m_webView->layerTreeView())
         return treeView->haveScrollEventHandlers();
     return false;
 }
 
 void ChromeClientImpl::setTouchAction(TouchAction touchAction)
 {
     if (WebViewClient* client = m_webView->client())
         client->setTouchAction(static_cast<WebTouchAction>(touchAction));
@@ skipping 144 matching lines @@
     if (m_webView->pageImportanceSignals())
         m_webView->pageImportanceSignals()->setIssuedNonGetFetchFromScript();
 }
 
 PassOwnPtr<WebFrameScheduler> ChromeClientImpl::createFrameScheduler(BlameContext* blameContext)
 {
     return adoptPtr(m_webView->scheduler()->createFrameScheduler(blameContext).release());
 }
 
 } // namespace blink