Canvas2d: Implement rerouting event by hit region's control.

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

Index: third_party/WebKit/Source/core/input/EventHandler.cpp
diff --git a/third_party/WebKit/Source/core/input/EventHandler.cpp b/third_party/WebKit/Source/core/input/EventHandler.cpp
index 5ec337e655cfa8a1cfe03b4df1cb535a050dfb01..8c73004514e9e6197dca392c5b3ae87ba475aff4 100644
--- a/third_party/WebKit/Source/core/input/EventHandler.cpp
+++ b/third_party/WebKit/Source/core/input/EventHandler.cpp
@@ -56,6 +56,7 @@
 #include "core/frame/LocalFrame.h"
 #include "core/frame/Settings.h"
 #include "core/frame/VisualViewport.h"
+#include "core/html/HTMLCanvasElement.h"
 #include "core/html/HTMLDialogElement.h"
 #include "core/html/HTMLFrameElementBase.h"
 #include "core/html/HTMLFrameSetElement.h"
@@ -359,6 +360,7 @@ DEFINE_TRACE(EventHandler)
     visitor->trace(m_previousWheelScrolledNode);
     visitor->trace(m_scrollbarHandlingScrollGesture);
     visitor->trace(m_targetForTouchID);
+    visitor->trace(m_regionForTouchID);
     visitor->trace(m_touchSequenceDocument);
     visitor->trace(m_scrollGestureHandlingNode);
     visitor->trace(m_previousGestureScrolledNode);
@@ -3844,7 +3846,8 @@ WebInputEventResult EventHandler::dispatchTouchEvents(const PlatformTouchEvent&
             touchInfo.adjustedPagePoint,
             touchInfo.adjustedRadius,
             point.rotationAngle(),
-            point.force());
+            point.force(),
+            touchInfo.region);
 
         // Ensure this target's touch list exists, even if it ends up empty, so
         // it can always be passed to TouchEvent::Create below.
@@ -3971,6 +3974,13 @@ WebInputEventResult EventHandler::handleTouchEvent(const PlatformTouchEvent& eve
             if (!node)
                 continue;
 
+            if (isHTMLCanvasElement(node)) {
+                std::pair<Element*, String> regionInfo = toHTMLCanvasElement(node)->getControlAndIDIfHitRegionExists(result.pointInInnerNodeFrame());
+                if (regionInfo.first)
+                    node = regionInfo.first;
+                m_regionForTouchID.set(point.id(), regionInfo.second);
+            }
+
             // Touch events should not go to text nodes
             if (node->isTextNode())
                 node = ComposedTreeTraversal::parent(*node);
@@ -4017,16 +4027,19 @@ WebInputEventResult EventHandler::handleTouchEvent(const PlatformTouchEvent& eve
         const PlatformTouchPoint& point = points[i];
         PlatformTouchPoint::State pointState = point.state();
         RefPtrWillBeRawPtr<EventTarget> touchTarget = nullptr;
+        String regionID;
 
         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());
+            regionID = m_regionForTouchID.take(point.id());
         } else {
             // No hittest is performed on move or stationary, since the target
             // is not allowed to change anyway.
             touchTarget = m_targetForTouchID.get(point.id());
+            regionID = m_regionForTouchID.get(point.id());
         }
 
         LocalFrame* targetFrame = nullptr;
@@ -4072,6 +4085,7 @@ WebInputEventResult EventHandler::handleTouchEvent(const PlatformTouchEvent& eve
         touchInfo.adjustedRadius = point.radius().scaledBy(scaleFactor);
         touchInfo.knownTarget = knownTarget;
         touchInfo.consumed = false;
+        touchInfo.region = regionID;
     }
 
     if (!m_inPointerCanceledState) {