Improve detection of touch events when hiding media controls.

Source/core/events/MouseRelatedEvent.cpp

Index: Source/core/events/MouseRelatedEvent.cpp
diff --git a/Source/core/events/MouseRelatedEvent.cpp b/Source/core/events/MouseRelatedEvent.cpp
index 9b7f32ec3a37666eff6bb73e64b3b17a7e226d55..a2b513483893ba03a7572b9344b65b415029c775 100644
--- a/Source/core/events/MouseRelatedEvent.cpp
+++ b/Source/core/events/MouseRelatedEvent.cpp
@@ -35,6 +35,7 @@ namespace blink {
 MouseRelatedEvent::MouseRelatedEvent()
     : m_isSimulated(false)
     , m_hasCachedRelativePosition(false)
+    , m_derivesFromTouch(false)
 {
 }
 
@@ -52,14 +53,15 @@ static LayoutSize contentsScrollOffset(AbstractView* abstractView)
     return LayoutSize(frameView->scrollX() / scaleFactor, frameView->scrollY() / scaleFactor);
 }
 
-MouseRelatedEvent::MouseRelatedEvent(const AtomicString& eventType, bool canBubble, bool cancelable, PassRefPtrWillBeRawPtr<AbstractView> abstractView,
-                                     int detail, const IntPoint& screenLocation, const IntPoint& windowLocation,
-                                     const IntPoint& movementDelta,
-                                     bool ctrlKey, bool altKey, bool shiftKey, bool metaKey, bool isSimulated)
+MouseRelatedEvent::MouseRelatedEvent(const AtomicString& eventType, bool canBubble, bool cancelable,
+    PassRefPtrWillBeRawPtr<AbstractView> abstractView, int detail, const IntPoint& screenLocation,
+    const IntPoint& windowLocation, const IntPoint& movementDelta, bool ctrlKey, bool altKey,
+    bool shiftKey, bool metaKey, bool isSimulated, bool derivesFromTouch)
     : UIEventWithKeyState(eventType, canBubble, cancelable, abstractView, detail, ctrlKey, altKey, shiftKey, metaKey)
     , m_screenLocation(screenLocation)
     , m_movementDelta(movementDelta)
     , m_isSimulated(isSimulated)
+    , m_derivesFromTouch(derivesFromTouch)
 {
     LayoutPoint adjustedPageLocation;
     LayoutPoint scrollPosition;