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third_party/WebKit/Source/web/WebViewImpl.cpp

Index: third_party/WebKit/Source/web/WebViewImpl.cpp
diff --git a/third_party/WebKit/Source/web/WebViewImpl.cpp b/third_party/WebKit/Source/web/WebViewImpl.cpp
index 27b2257ce476d635243430b6c24a9933cf7077e6..71ded6d99fd611eefd2e2df4b744990ddd37115b 100644
--- a/third_party/WebKit/Source/web/WebViewImpl.cpp
+++ b/third_party/WebKit/Source/web/WebViewImpl.cpp
@@ -437,7 +437,7 @@ WebViewImpl::WebViewImpl(WebViewClient* client)
     , m_matchesHeuristicsForGpuRasterization(false)
     , m_recreatingGraphicsContext(false)
     , m_flingModifier(0)
-    , m_flingSourceDevice(false)
+    , m_flingSourceDevice(WebGestureDeviceUninitialized)
     , m_fullscreenController(FullscreenController::create(this))
     , m_showFPSCounter(false)
     , m_baseBackgroundColor(Color::white)
@@ -642,6 +642,7 @@ bool WebViewImpl::handleMouseWheel(LocalFrame& mainFrame, const WebMouseWheelEve
 
 bool WebViewImpl::scrollBy(const WebFloatSize& delta, const WebFloatSize& velocity)
 {
+    ASSERT(m_flingSourceDevice != WebGestureDeviceUninitialized);
     if (m_flingSourceDevice == WebGestureDeviceTouchpad) {
         WebMouseWheelEvent syntheticWheel;
         const float tickDivisor = WheelEvent::TickMultiplier;
@@ -913,6 +914,7 @@ void WebViewImpl::transferActiveWheelFlingAnimation(const WebActiveWheelFlingPar
     OwnPtr<WebGestureCurve> curve = adoptPtr(Platform::current()->createFlingAnimationCurve(parameters.sourceDevice, WebFloatPoint(parameters.delta), parameters.cumulativeScroll));
     ASSERT(curve);
     m_gestureAnimation = WebActiveGestureAnimation::createWithTimeOffset(curve.release(), this, parameters.startTime);
+    m_flingSourceDevice = parameters.sourceDevice;
     scheduleAnimation();
 }
 
@@ -920,6 +922,7 @@ bool WebViewImpl::endActiveFlingAnimation()
 {
     if (m_gestureAnimation) {
         m_gestureAnimation.clear();
+        m_flingSourceDevice = WebGestureDeviceUninitialized;
         if (m_layerTreeView)
             m_layerTreeView->didStopFlinging();
         return true;
@@ -1872,9 +1875,10 @@ void WebViewImpl::beginFrame(const WebBeginFrameArgs& frameTime)
         else {
             endActiveFlingAnimation();
 
+            ASSERT(m_flingSourceDevice != WebGestureDeviceUninitialized);
             PlatformGestureEvent endScrollEvent(PlatformEvent::GestureScrollEnd,
                 m_positionOnFlingStart, m_globalPositionOnFlingStart,
-                IntSize(), 0, PlatformEvent::NoModifiers);
+                IntSize(), 0, PlatformEvent::NoModifiers, m_flingSourceDevice == WebGestureDeviceTouchpad ? PlatformGestureSourceTouchpad : PlatformGestureSourceTouchscreen);
             endScrollEvent.setScrollGestureData(0, 0, 0, 0, true, false, -1 /* null plugin id */);
 
             mainFrameImpl()->frame()->eventHandler().handleGestureScrollEnd(endScrollEvent);