Make EventHandler::ActiveIntervalTimer mockable.

Source/core/page/EventHandler.cpp

Index: Source/core/page/EventHandler.cpp
diff --git a/Source/core/page/EventHandler.cpp b/Source/core/page/EventHandler.cpp
index 9be96d9363384ea8520ab304fb6bf7c3f4e013c1..5a2f0b683aecbe4d2a243942eb931963959ca7d2 100755
--- a/Source/core/page/EventHandler.cpp
+++ b/Source/core/page/EventHandler.cpp
@@ -2738,6 +2738,11 @@ bool EventHandler::bestZoomableAreaForTouchPoint(const IntPoint& touchCenter, co
     return findBestZoomableArea(targetNode, targetArea, touchCenter, touchRect, Vector<RefPtr<Node> >(nodes));
 }
 
+MockableTimer<EventHandler>* EventHandler::activeIntervalTimerForTesting()
+{
+    return &m_activeIntervalTimer;
+}
+
 bool EventHandler::adjustGesturePosition(const PlatformGestureEvent& gestureEvent, IntPoint& adjustedPoint)
 {
     if (!shouldApplyTouchAdjustment(gestureEvent))