Merge WebKit at r78450: Initial merge by git.

Change-Id: I6d3e5f1f868ec266a0aafdef66182ddc3f265dc1

1 files changed, 41 insertions, 0 deletions

diff --git a/Source/WebCore/platform/ScrollAnimator.cpp b/Source/WebCore/platform/ScrollAnimator.cpp
index 428a79d..6fc78e7 100644
--- a/Source/WebCore/platform/ScrollAnimator.cpp
+++ b/Source/WebCore/platform/ScrollAnimator.cpp
@@ -32,10 +32,13 @@
 #include "ScrollAnimator.h"
 
 #include "FloatPoint.h"
+#include "PlatformWheelEvent.h"
 #include "ScrollableArea.h"
 #include <algorithm>
 #include <wtf/PassOwnPtr.h>
 
+using namespace std;
+
 namespace WebCore {
 
 #if !ENABLE(SMOOTH_SCROLLING)
@@ -78,6 +81,44 @@ void ScrollAnimator::scrollToOffsetWithoutAnimation(const FloatPoint& offset)
     }
 }
 
+void ScrollAnimator::handleWheelEvent(PlatformWheelEvent& e)
+{
+    Scrollbar* horizontalScrollbar = m_scrollableArea->horizontalScrollbar();
+    Scrollbar* verticalScrollbar = m_scrollableArea->verticalScrollbar();
+
+    // Accept the event if we have a scrollbar in that direction and can still
+    // scroll any further.
+    float deltaX = horizontalScrollbar ? e.deltaX() : 0;
+    float deltaY = verticalScrollbar ? e.deltaY() : 0;
+
+    IntSize maxForwardScrollDelta = m_scrollableArea->maximumScrollPosition() - m_scrollableArea->scrollPosition();
+    IntSize maxBackwardScrollDelta = m_scrollableArea->scrollPosition() - m_scrollableArea->minimumScrollPosition();
+    if ((deltaX < 0 && maxForwardScrollDelta.width() > 0)
+        || (deltaX > 0 && maxBackwardScrollDelta.width() > 0)
+        || (deltaY < 0 && maxForwardScrollDelta.height() > 0)
+        || (deltaY > 0 && maxBackwardScrollDelta.height() > 0)) {
+        e.accept();
+        if (e.granularity() == ScrollByPageWheelEvent) {
+            ASSERT(!e.deltaX());
+            bool negative = deltaY < 0;
+            deltaY = max(max(static_cast<float>(m_scrollableArea->visibleHeight()) * Scrollbar::minFractionToStepWhenPaging(), static_cast<float>(m_scrollableArea->visibleHeight() - Scrollbar::maxOverlapBetweenPages())), 1.0f);
+            if (negative)
+                deltaY = -deltaY;
+        }
+
+        if (deltaY)
+            scroll(VerticalScrollbar, ScrollByPixel, verticalScrollbar->pixelStep(), -deltaY);
+        if (deltaX)
+            scroll(HorizontalScrollbar, ScrollByPixel, horizontalScrollbar->pixelStep(), -deltaX);
+    }
+}
+
+#if ENABLE(GESTURE_EVENTS)
+void ScrollAnimator::handleGestureEvent(const PlatformGestureEvent&)
+{
+}
+#endif
+
 FloatPoint ScrollAnimator::currentPosition() const
 {
     return FloatPoint(m_currentPosX, m_currentPosY);