Remove PlatformGestureEvent in favour of using WebGestureEvent

third_party/WebKit/Source/platform/scroll/Scrollbar.cpp

Index: third_party/WebKit/Source/platform/scroll/Scrollbar.cpp
diff --git a/third_party/WebKit/Source/platform/scroll/Scrollbar.cpp b/third_party/WebKit/Source/platform/scroll/Scrollbar.cpp
index 516eed533a8be643ee4b9a1c0b32f7df95180df5..2d7adf6ec53e962f116ed486f9156abcf0d7238e 100644
--- a/third_party/WebKit/Source/platform/scroll/Scrollbar.cpp
+++ b/third_party/WebKit/Source/platform/scroll/Scrollbar.cpp
@@ -27,13 +27,13 @@
 
 #include <algorithm>
 #include "platform/HostWindow.h"
-#include "platform/PlatformGestureEvent.h"
 #include "platform/PlatformMouseEvent.h"
 #include "platform/geometry/FloatRect.h"
 #include "platform/graphics/paint/CullRect.h"
 #include "platform/scroll/ScrollAnimatorBase.h"
 #include "platform/scroll/ScrollableArea.h"
 #include "platform/scroll/ScrollbarTheme.h"
+#include "public/platform/WebGestureEvent.h"
 
 namespace blink {
 
@@ -320,25 +320,27 @@ void Scrollbar::setPressedPart(ScrollbarPart part) {
   m_pressedPart = part;
 }
 
-bool Scrollbar::gestureEvent(const PlatformGestureEvent& evt,
+bool Scrollbar::gestureEvent(const WebGestureEvent& evt,
                              bool* shouldUpdateCapture) {
   DCHECK(shouldUpdateCapture);
-  switch (evt.type()) {
-    case PlatformEvent::GestureTapDown:
-      setPressedPart(theme().hitTest(*this, evt.position()));
+  switch (evt.type) {
+    case WebInputEvent::GestureTapDown: {
+      IntPoint position = flooredIntPoint(evt.positionInRootFrame());
+      setPressedPart(theme().hitTest(*this, position));
       m_pressedPos = orientation() == HorizontalScrollbar
-                         ? convertFromRootFrame(evt.position()).x()
-                         : convertFromRootFrame(evt.position()).y();
+                         ? convertFromRootFrame(position).x()
+                         : convertFromRootFrame(position).y();
       *shouldUpdateCapture = true;
       return true;
-    case PlatformEvent::GestureTapDownCancel:
+    }
+    case WebInputEvent::GestureTapCancel:
       if (m_pressedPart != ThumbPart)
         return false;
       m_scrollPos = m_pressedPos;
       return true;
-    case PlatformEvent::GestureScrollBegin:
-      switch (evt.source()) {
-        case PlatformGestureSourceTouchpad:
+    case WebInputEvent::GestureScrollBegin:
+      switch (evt.sourceDevice) {
+        case WebGestureDeviceTouchpad:
           // Update the state on GSB for touchpad since GestureTapDown
           // is not generated by that device. Touchscreen uses the tap down
           // gesture since the scrollbar enters a visual active state.
@@ -346,7 +348,7 @@ bool Scrollbar::gestureEvent(const PlatformGestureEvent& evt,
           setPressedPart(NoPart);
           m_pressedPos = 0;
           return true;
-        case PlatformGestureSourceTouchscreen:
+        case WebGestureDeviceTouchscreen:
           if (m_pressedPart != ThumbPart)
             return false;
           m_scrollPos = m_pressedPos;
@@ -356,22 +358,25 @@ bool Scrollbar::gestureEvent(const PlatformGestureEvent& evt,
           return true;
       }
       break;
-    case PlatformEvent::GestureScrollUpdate:
-      switch (evt.source()) {
-        case PlatformGestureSourceTouchpad: {
-          FloatSize delta(-evt.deltaX(), -evt.deltaY());
+    case WebInputEvent::GestureScrollUpdate:
+      switch (evt.sourceDevice) {
+        case WebGestureDeviceTouchpad: {
+          FloatSize delta(-evt.deltaXInRootFrame(), -evt.deltaYInRootFrame());
           if (m_scrollableArea &&
-              m_scrollableArea->userScroll(evt.deltaUnits(), delta)
+              m_scrollableArea
+                  ->userScroll(toPlatformScrollGranularity(evt.deltaUnits()),
+                               delta)
                   .didScroll()) {
             return true;
           }
           return false;
         }
-        case PlatformGestureSourceTouchscreen:
+        case WebGestureDeviceTouchscreen:
           if (m_pressedPart != ThumbPart)
             return false;
-          m_scrollPos += orientation() == HorizontalScrollbar ? evt.deltaX()
-                                                              : evt.deltaY();
+          m_scrollPos += orientation() == HorizontalScrollbar
+                             ? evt.deltaXInRootFrame()
+                             : evt.deltaYInRootFrame();
           moveThumb(m_scrollPos, false);
           return true;
         default:
@@ -379,14 +384,14 @@ bool Scrollbar::gestureEvent(const PlatformGestureEvent& evt,
           return true;
       }
       break;
-    case PlatformEvent::GestureScrollEnd:
-    case PlatformEvent::GestureLongPress:
-    case PlatformEvent::GestureFlingStart:
+    case WebInputEvent::GestureScrollEnd:
+    case WebInputEvent::GestureLongPress:
+    case WebInputEvent::GestureFlingStart:
       m_scrollPos = 0;
       m_pressedPos = 0;
       setPressedPart(NoPart);
       return false;
-    case PlatformEvent::GestureTap: {
+    case WebInputEvent::GestureTap: {
       if (m_pressedPart != ThumbPart && m_pressedPart != NoPart &&
           m_scrollableArea &&
           m_scrollableArea