Added PointerEvent firing on touch events.

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 27 matching lines @@
 #include "core/dom/TouchList.h"
 #include "core/dom/shadow/ComposedTreeTraversal.h"
 #include "core/dom/shadow/ShadowRoot.h"
 #include "core/editing/Editor.h"
 #include "core/editing/FrameSelection.h"
 #include "core/editing/htmlediting.h"
 #include "core/editing/iterators/TextIterator.h"
 #include "core/events/EventPath.h"
 #include "core/events/KeyboardEvent.h"
 #include "core/events/MouseEvent.h"
+#include "core/events/PointerEvent.h"
 #include "core/events/TextEvent.h"
 #include "core/events/TouchEvent.h"
 #include "core/events/WheelEvent.h"
 #include "core/fetch/ImageResource.h"
 #include "core/frame/EventHandlerRegistry.h"
 #include "core/frame/FrameHost.h"
 #include "core/frame/FrameView.h"
 #include "core/frame/LocalFrame.h"
 #include "core/frame/PinchViewport.h"
 #include "core/frame/Settings.h"
@@ skipping 172 matching lines @@
     , m_fakeMouseMoveEventTimer(this, &EventHandler::fakeMouseMoveEventTimerFired)
     , m_svgPan(false)
     , m_resizeScrollableArea(nullptr)
     , m_eventHandlerWillResetCapturingMouseEventsNode(0)
     , m_clickCount(0)
     , m_shouldOnlyFireDragOverEvent(false)
     , m_mousePositionIsUnknown(true)
     , m_mouseDownTimestamp(0)
     , m_widgetIsLatched(false)
     , m_touchPressed(false)
+    , m_primaryPointerId(0)
     , m_scrollGestureHandlingNode(nullptr)
     , m_lastGestureScrollOverWidget(false)
     , m_maxMouseMovedDuration(0)
     , m_longTapShouldInvokeContextMenu(false)
     , m_activeIntervalTimer(this, &EventHandler::activeIntervalTimerFired)
     , m_lastShowPressTimestamp(0)
     , m_deltaConsumedForScrollSequence(false)
 {
 }
 
@@ skipping 60 matching lines @@
     m_previousWheelScrolledNode = nullptr;
     m_targetForTouchID.clear();
     m_touchSequenceDocument.clear();
     m_touchSequenceUserGestureToken.clear();
     m_scrollGestureHandlingNode = nullptr;
     m_lastGestureScrollOverWidget = false;
     m_previousGestureScrolledNode = nullptr;
     m_scrollbarHandlingScrollGesture = nullptr;
     m_maxMouseMovedDuration = 0;
     m_touchPressed = false;
+    m_primaryPointerId = 0;
     m_mouseDownMayStartSelect = false;
     m_mouseDownMayStartDrag = false;
     m_lastShowPressTimestamp = 0;
     m_lastDeferredTapElement = nullptr;
     m_eventHandlerWillResetCapturingMouseEventsNode = false;
     m_mouseDownWasSingleClickInSelection = false;
     m_selectionInitiationState = HaveNotStartedSelection;
     m_mouseDownMayStartAutoscroll = false;
     m_svgPan = false;
     m_mouseDownPos = IntPoint();
@@ skipping 3439 matching lines @@
             m_lastScrollbarUnderMouse->mouseExited();
 
         // Send mouse entered if we're setting a new scrollbar.
         if (scrollbar && setLast)
             scrollbar->mouseEntered();
 
         m_lastScrollbarUnderMouse = setLast ? scrollbar : nullptr;
     }
 }
 
-static const AtomicString& eventNameForTouchPointState(PlatformTouchPoint::State state)
+static const AtomicString& touchEventNameForTouchPointState(PlatformTouchPoint::State state)
 {
     switch (state) {
     case PlatformTouchPoint::TouchReleased:
         return EventTypeNames::touchend;
     case PlatformTouchPoint::TouchCancelled:
         return EventTypeNames::touchcancel;
     case PlatformTouchPoint::TouchPressed:
         return EventTypeNames::touchstart;
     case PlatformTouchPoint::TouchMoved:
         return EventTypeNames::touchmove;
     case PlatformTouchPoint::TouchStationary:
         // TouchStationary state is not converted to touch events, so fall through to assert.
     default:
         ASSERT_NOT_REACHED();
         return emptyAtom;
     }
 }
 
+static const AtomicString& pointerEventNameForTouchPointState(PlatformTouchPoint::State state)
+{
+    switch (state) {
+    case PlatformTouchPoint::TouchReleased:
+        return EventTypeNames::pointerup;
+    case PlatformTouchPoint::TouchCancelled:
+        return EventTypeNames::pointercancel;
+    case PlatformTouchPoint::TouchPressed:
+        return EventTypeNames::pointerdown;
+    case PlatformTouchPoint::TouchMoved:
+        return EventTypeNames::pointermove;
+    case PlatformTouchPoint::TouchStationary:
+        // TouchStationary state is not converted to touch events, so fall through to assert.
+    default:
+        ASSERT_NOT_REACHED();
+        return emptyAtom;
+    }
+}
+
 HitTestResult EventHandler::hitTestResultInFrame(LocalFrame* frame, const LayoutPoint& point, HitTestRequest::HitTestRequestType hitType)
 {
     HitTestResult result(HitTestRequest(hitType), point);
 
     if (!frame || !frame->contentLayoutObject())
         return result;
     if (frame->view()) {
         IntRect rect = frame->view()->visibleContentRect(IncludeScrollbars);
         if (!rect.contains(roundedIntPoint(point)))
             return result;
     }
     frame->contentLayoutObject()->hitTest(result);
     return result;
 }
 
 bool EventHandler::handleTouchEvent(const PlatformTouchEvent& event)
 {
     TRACE_EVENT0("blink", "EventHandler::handleTouchEvent");
 
     const Vector<PlatformTouchPoint>& points = event.touchPoints();
 
-    unsigned i;
     bool freshTouchEvents = true;
     bool allTouchReleased = true;
-    for (i = 0; i < points.size(); ++i) {
+    for (unsigned i = 0; i < points.size(); ++i) {
         const PlatformTouchPoint& point = points[i];
         if (point.state() != PlatformTouchPoint::TouchPressed)
             freshTouchEvents = false;
         if (point.state() != PlatformTouchPoint::TouchReleased && point.state() != PlatformTouchPoint::TouchCancelled)
             allTouchReleased = false;
     }
     if (freshTouchEvents) {
         // Ideally we'd ASSERT !m_touchSequenceDocument here since we should
         // have cleared the active document when we saw the last release. But we
         // have some tests that violate this, ClusterFuzz could trigger it, and
@@ skipping 13 matching lines @@
     m_touchSequenceUserGestureToken = gestureIndicator->currentToken();
 
     ASSERT(m_frame->view());
     if (m_touchSequenceDocument && (!m_touchSequenceDocument->frame() || !m_touchSequenceDocument->frame()->view())) {
         // If the active touch document has no frame or view, it's probably being destroyed
         // so we can't dispatch events.
         return false;
     }
 
     // First do hit tests for any new touch points.
-    for (i = 0; i < points.size(); ++i) {
+    for (unsigned i = 0; i < points.size(); ++i) {
         const PlatformTouchPoint& point = points[i];
 
         // Touch events implicitly capture to the touched node, and don't change
         // active/hover states themselves (Gesture events do). So we only need
         // to hit-test on touchstart, and it can be read-only.
         if (point.state() == PlatformTouchPoint::TouchPressed) {
             HitTestRequest::HitTestRequestType hitType = HitTestRequest::TouchEvent | HitTestRequest::ReadOnly | HitTestRequest::Active;
             LayoutPoint pagePoint = roundedLayoutPoint(m_frame->view()->rootFrameToContents(point.pos()));
             HitTestResult result;
             if (!m_touchSequenceDocument) {
@@ skipping 14 matching lines @@
                 node = ComposedTreeTraversal::parent(*node);
 
             if (!m_touchSequenceDocument) {
                 // Keep track of which document should receive all touch events
                 // in the active sequence. This must be a single document to
                 // ensure we don't leak Nodes between documents.
                 m_touchSequenceDocument = &(result.innerNode()->document());
                 ASSERT(m_touchSequenceDocument->frame()->view());
             }
 
+            // If it is the first TouchPressed we have seen so far, we will consider it primary.
+            if (!m_primaryPointerId)
+                m_primaryPointerId = point.id();
+
             // Ideally we'd ASSERT(!m_targetForTouchID.contains(point.id())
             // since we shouldn't get a touchstart for a touch that's already
             // down. However EventSender allows this to be violated and there's
             // some tests that take advantage of it. There may also be edge
             // cases in the browser where this happens.
             // See http://crbug.com/345372.
             m_targetForTouchID.set(point.id(), node);
 
             TouchAction effectiveTouchAction = computeEffectiveTouchAction(*node);
             if (effectiveTouchAction != TouchActionAuto)
                 m_frame->page()->chrome().client().setTouchAction(effectiveTouchAction);
         }
     }
 
     m_touchPressed = !allTouchReleased;
 
+    unsigned lastPrimaryPointerId = m_primaryPointerId;
+    if (allTouchReleased)
+        m_primaryPointerId = 0;
+
     // If there's no document receiving touch events, or no handlers on the
     // document set to receive the events, then we can skip all the rest of
     // this work.
     if (!m_touchSequenceDocument || !m_touchSequenceDocument->frameHost() || !m_touchSequenceDocument->frameHost()->eventHandlerRegistry().hasEventHandlers(EventHandlerRegistry::TouchEvent) || !m_touchSequenceDocument->frame()) {
         if (allTouchReleased) {
             m_touchSequenceDocument.clear();
             m_touchSequenceUserGestureToken.clear();
         }
         return false;
     }
@@ skipping 14 matching lines @@
     // Array of touches per state, used to assemble the 'changedTouches' list.
     using EventTargetSet = WillBeHeapHashSet<RefPtrWillBeMember<EventTarget>>;
     struct {
         // The touches corresponding to the particular change state this struct
         // instance represents.
         RefPtrWillBeMember<TouchList> m_touches;
         // Set of targets involved in m_touches.
         EventTargetSet m_targets;
     } changedTouches[PlatformTouchPoint::TouchStateEnd];
 
-    for (i = 0; i < points.size(); ++i) {
+    for (unsigned i = 0; i < points.size(); ++i) {
         const PlatformTouchPoint& point = points[i];
         PlatformTouchPoint::State pointState = point.state();
         RefPtrWillBeRawPtr<EventTarget> touchTarget = nullptr;
 
         if (pointState == PlatformTouchPoint::TouchReleased || pointState == PlatformTouchPoint::TouchCancelled) {
             // The target should be the original target for this touch, so get
             // it from the hashmap. As it's a release or cancel we also remove
             // it from the map.
             touchTarget = m_targetForTouchID.take(point.id());
         } else {
@@ skipping 72 matching lines @@
                 changedTouches[pointState].m_touches = TouchList::create();
             changedTouches[pointState].m_touches->append(touch);
             changedTouches[pointState].m_targets.add(touchTarget);
         }
     }
     if (allTouchReleased) {
         m_touchSequenceDocument.clear();
         m_touchSequenceUserGestureToken.clear();
     }
 
-    // Now iterate the changedTouches list and m_targets within it, sending
-    // events to the targets as required.
     bool swallowedEvent = false;
+
+    // Iterate the changedTouches list and m_targets within it, sending PointerEvents
+    // to the targets as required.

[Rick Byers, 2015/05/25 18:24:26]

I think you'll want to skip all this if your RuntimeEnabledFeature is disabled
(just to make sure we're not adding any overhead in that case).

[mustaq, 2015/05/26 15:00:09]

Done. See my next comment on cleanup.

     for (unsigned state = 0; state != PlatformTouchPoint::TouchStateEnd; ++state) {
         if (!changedTouches[state].m_touches)
             continue;
 
-        const AtomicString& stateName(eventNameForTouchPointState(static_cast<PlatformTouchPoint::State>(state)));
+        const AtomicString& eventName(pointerEventNameForTouchPointState(static_cast<PlatformTouchPoint::State>(state)));
+        const EventTargetSet& targetsForState = changedTouches[state].m_targets;
+
+        for (const RefPtrWillBeMember<EventTarget>& eventTarget : targetsForState) {
+            EventTarget* pointerEventTarget = eventTarget.get();
+            TouchList* touchesForTarget = touchesByTarget.get(pointerEventTarget);

[Rick Byers, 2015/05/25 18:24:26]

I think this would be simpler if you didn't use the indexes eg.
(targetsForState), they're needed only for creating the complicated touchlists
specific to touch events.  In fact, looking to the future (where TE support is
an optional component on top of PE) we'll want to avoid creating them in the
first place unless some pointer event goes unhandled and there is a touch event.
 So perhaps this dispatching pointer event logic could be moved up above line
3947 and then iterate over the points directly (since there's a 1:1
correspondence between the input points and the generated pointer events). 
You'll then need to track some "pointer event was consumed" bit per point.

Maybe it would even make sense to change any point which had a consumed pointer
event to the 'stationary' state?  I.e. if the events are consumed for one finger
but not another, then we'd fire touchmove with only a single changedTouch?  This
will ultimately need to be part of whatever touch/pointer interoperability doc
we produce in the TECG, but seems like a reasonable place to start to me.  I
don't think the current behavior (where eg. consuming only pointermove could
suppress generation of touchstart/touchend) is likely to be where we want to
land.

[mustaq, 2015/05/26 15:00:09]

I agree on your first point. I will isolate the indices from PE code soon, still
trying to discover the missing PEs.

Re firing TEs for "partially consumed" PEs, I think this would lead to
unnecessary complications for developers. The simplest model for the developers
could be: "handle either PE or TE, not both". If we allow complex PE+TE handling
(e.g. "can consume touchstart, yet can see pointermove"), this would leave too
many corner cases open for developers, and encourage out-of-spec web-pages by
naive ones which is bad for the long-term health of the web. Am I missing
something here?

+            for (unsigned i = 0; i < touchesForTarget->length(); i++) {
+                Touch* touch = touchesForTarget->item(i);
+
+                PointerEventInit pointerEventInit;
+                pointerEventInit.setPointerId(touch->identifier());
+                pointerEventInit.setWidth(touch->radiusX());
+                pointerEventInit.setHeight(touch->radiusY());
+                pointerEventInit.setPressure(touch->force());
+                pointerEventInit.setTiltX(0.0);
+                pointerEventInit.setTiltY(0.0);
+                pointerEventInit.setPointerType(eventName);
+                pointerEventInit.setIsPrimary(lastPrimaryPointerId == touch->identifier());
+
+                RefPtrWillBeRawPtr<PointerEvent> pointerEvent = PointerEvent::create(eventName, pointerEventInit);
+                pointerEventTarget->toNode()->dispatchPointerEvent(pointerEvent.get());
+                swallowedEvent = swallowedEvent || pointerEvent->defaultPrevented() || pointerEvent->defaultHandled();
+            }
+        }
+    }
+
+    // Skip firing TouchEvent's if any PointerEvent was consumed.
+    if (swallowedEvent)
+        return true;
+
+    // Now iterate the changedTouches list and m_targets within it, sending
+    // TouchEvents to the targets as required.
+    for (unsigned state = 0; state != PlatformTouchPoint::TouchStateEnd; ++state) {
+        if (!changedTouches[state].m_touches)
+            continue;
+
+        const AtomicString& eventName(touchEventNameForTouchPointState(static_cast<PlatformTouchPoint::State>(state)));
         const EventTargetSet& targetsForState = changedTouches[state].m_targets;
         for (const RefPtrWillBeMember<EventTarget>& eventTarget : targetsForState) {
             EventTarget* touchEventTarget = eventTarget.get();
             RefPtrWillBeRawPtr<TouchEvent> touchEvent = TouchEvent::create(
                 touches.get(), touchesByTarget.get(touchEventTarget), changedTouches[state].m_touches.get(),
-                stateName, touchEventTarget->toNode()->document().domWindow(),
+                eventName, touchEventTarget->toNode()->document().domWindow(),
                 event.ctrlKey(), event.altKey(), event.shiftKey(), event.metaKey(), event.cancelable(), event.causesScrollingIfUncanceled(), event.timestamp());
             touchEventTarget->toNode()->dispatchTouchEvent(touchEvent.get());
             swallowedEvent = swallowedEvent || touchEvent->defaultPrevented() || touchEvent->defaultHandled();
         }
     }
 
     return swallowedEvent;
 }
 
 TouchAction EventHandler::intersectTouchAction(TouchAction action1, TouchAction action2)
@@ skipping 111 matching lines @@
 unsigned EventHandler::accessKeyModifiers()
 {
 #if OS(MACOSX)
     return PlatformEvent::CtrlKey | PlatformEvent::AltKey;
 #else
     return PlatformEvent::AltKey;
 #endif
 }
 
 } // namespace blink