Remove mouse-related hit tests during a GestureTap

Source/core/page/EventHandler.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2012 Digia Plc. 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
@@ skipping 1209 matching lines @@
     m_mouseDownMayStartSelect = false;
     m_mouseDownMayStartAutoscroll = false;
     if (FrameView* view = m_frame->view())
         m_mouseDownPos = view->windowToContents(mouseEvent.position());
     else {
         invalidateClick();
         return false;
     }
     m_mouseDownWasInSubframe = false;
 
-    HitTestRequest::HitTestRequestType hitType = HitTestRequest::Active;
-    if (mouseEvent.fromTouch())
-        hitType |= HitTestRequest::ReadOnly;
-    HitTestRequest request(hitType);
+    // Mouse events simulated from touch should not hit-test again.
+    ASSERT(!mouseEvent.fromTouch());
+
+    HitTestRequest request(HitTestRequest::Active);
     // Save the document point we generate in case the window coordinate is invalidated by what happens
     // when we dispatch the event.
     LayoutPoint documentPoint = documentPointForWindowPoint(m_frame, mouseEvent.position());
     MouseEventWithHitTestResults mev = m_frame->document()->prepareMouseEvent(request, documentPoint, mouseEvent);
 
     if (!mev.targetNode()) {
         invalidateClick();
         return false;
     }
 
@@ skipping 158 matching lines @@
 
     if (m_frameSetBeingResized)
         return !dispatchMouseEvent(EventTypeNames::mousemove, m_frameSetBeingResized.get(), 0, mouseEvent, false);
 
     // Send events right to a scrollbar if the mouse is pressed.
     if (m_lastScrollbarUnderMouse && m_mousePressed) {
         m_lastScrollbarUnderMouse->mouseMoved(mouseEvent);
         return true;
     }
 
+    // Mouse events simulated from touch should not hit-test again.
+    ASSERT(!mouseEvent.fromTouch());
+
     HitTestRequest::HitTestRequestType hitType = HitTestRequest::Move;
-    if (mouseEvent.fromTouch())
-        hitType |= HitTestRequest::ReadOnly;
-
     if (m_mousePressed)
         hitType |= HitTestRequest::Active;
     else if (onlyUpdateScrollbars) {
         // Mouse events should be treated as "read-only" if we're updating only scrollbars. This
         // means that :hover and :active freeze in the state they were in, rather than updating
         // for nodes the mouse moves while the window is not key (which will be the case if
         // onlyUpdateScrollbars is true).
         hitType |= HitTestRequest::ReadOnly;
     }
 
@@ skipping 107 matching lines @@
     if (m_frameSetBeingResized)
         return !dispatchMouseEvent(EventTypeNames::mouseup, m_frameSetBeingResized.get(), m_clickCount, mouseEvent, false);
 
     if (m_lastScrollbarUnderMouse) {
         invalidateClick();
         m_lastScrollbarUnderMouse->mouseUp(mouseEvent);
         bool setUnder = false;
         return !dispatchMouseEvent(EventTypeNames::mouseup, m_lastNodeUnderMouse.get(), m_clickCount, mouseEvent, setUnder);
     }
 
+    // Mouse events simulated from touch should not hit-test again.
+    ASSERT(!mouseEvent.fromTouch());
+
     HitTestRequest::HitTestRequestType hitType = HitTestRequest::Release;
-    if (mouseEvent.fromTouch())
-        hitType |= HitTestRequest::ReadOnly;
     HitTestRequest request(hitType);
     MouseEventWithHitTestResults mev = prepareMouseEvent(request, mouseEvent);
     LocalFrame* subframe = m_capturingMouseEventsNode.get() ? subframeForTargetNode(m_capturingMouseEventsNode.get()) : subframeForHitTestResult(mev);
     if (m_eventHandlerWillResetCapturingMouseEventsNode)
         m_capturingMouseEventsNode = nullptr;
     if (subframe && passMouseReleaseEventToSubframe(mev, subframe))
         return true;
 
     bool swallowMouseUpEvent = !dispatchMouseEvent(EventTypeNames::mouseup, mev.targetNode(), m_clickCount, mouseEvent, false);
 
@@ skipping 648 matching lines @@
     default:
         ASSERT_NOT_REACHED();
     }
     return false;
 }
 
 bool EventHandler::handleGestureTap(const GestureEventWithHitTestResults& targetedEvent)
 {
     const PlatformGestureEvent& gestureEvent = targetedEvent.event();
 
-    // FIXME: Refactor this code to not hit test multiple times. We use the adjusted position to ensure that the correct node is targeted by the later redundant hit tests.
-
     unsigned modifierFlags = 0;
     if (gestureEvent.altKey())
         modifierFlags |= PlatformEvent::AltKey;
     if (gestureEvent.ctrlKey())
         modifierFlags |= PlatformEvent::CtrlKey;
     if (gestureEvent.metaKey())
         modifierFlags |= PlatformEvent::MetaKey;
     if (gestureEvent.shiftKey())
         modifierFlags |= PlatformEvent::ShiftKey;
     PlatformEvent::Modifiers modifiers = static_cast<PlatformEvent::Modifiers>(modifierFlags);
 
+    // We use the adjusted position so the application isn't surprised to see a event with
+    // co-ordinates outside the target's bounds.
     IntPoint adjustedPoint = gestureEvent.position();
 
     PlatformMouseEvent fakeMouseMove(adjustedPoint, gestureEvent.globalPosition(),
         NoButton, PlatformEvent::MouseMoved, /* clickCount */ 0,
         modifiers, PlatformMouseEvent::FromTouch, gestureEvent.timestamp());
-    handleMouseMoveEvent(fakeMouseMove);
+    dispatchMouseEvent(EventTypeNames::mousemove, targetedEvent.targetNode(), 0, fakeMouseMove, true);
 
-    bool defaultPrevented = false;
     PlatformMouseEvent fakeMouseDown(adjustedPoint, gestureEvent.globalPosition(),
         LeftButton, PlatformEvent::MousePressed, gestureEvent.tapCount(),
         modifiers, PlatformMouseEvent::FromTouch,  gestureEvent.timestamp());
-    defaultPrevented |= handleMousePressEvent(fakeMouseDown);
+    bool swallowEvent = !dispatchMouseEvent(EventTypeNames::mousedown, targetedEvent.targetNode(), gestureEvent.tapCount(), fakeMouseDown, true);
+    swallowEvent = swallowEvent || !handleMouseFocus(fakeMouseDown);
 
     PlatformMouseEvent fakeMouseUp(adjustedPoint, gestureEvent.globalPosition(),
         LeftButton, PlatformEvent::MouseReleased, gestureEvent.tapCount(),
         modifiers, PlatformMouseEvent::FromTouch,  gestureEvent.timestamp());
-    defaultPrevented |= handleMouseReleaseEvent(fakeMouseUp);
+    swallowEvent |= !dispatchMouseEvent(EventTypeNames::mouseup, targetedEvent.targetNode(), gestureEvent.tapCount(), fakeMouseUp, false);
+    swallowEvent |= !dispatchMouseEvent(EventTypeNames::click, targetedEvent.targetNode(), gestureEvent.tapCount(), fakeMouseUp, true);
 
-    return defaultPrevented;
+    return swallowEvent;
 }
 
 bool EventHandler::handleGestureLongPress(const GestureEventWithHitTestResults& targetedEvent)
 {
     const PlatformGestureEvent& gestureEvent = targetedEvent.event();
     IntPoint adjustedPoint = gestureEvent.position();
 
     // FIXME: Ideally we should try to remove the extra mouse-specific hit-tests here (re-using the
     // supplied HitTestResult), but that will require some overhaul of the touch drag-and-drop code
     // and LongPress is such a special scenario that it's unlikely to matter much in practice.
@@ skipping 1542 matching lines @@
 unsigned EventHandler::accessKeyModifiers()
 {
 #if OS(MACOSX)
     return PlatformEvent::CtrlKey | PlatformEvent::AltKey;
 #else
     return PlatformEvent::AltKey;
 #endif
 }
 
 } // namespace WebCore