Replace various ScrollableArea scroll methods with setScrollPosition

Source/platform/scroll/ScrollAnimator.cpp

Index: Source/platform/scroll/ScrollAnimator.cpp
diff --git a/Source/platform/scroll/ScrollAnimator.cpp b/Source/platform/scroll/ScrollAnimator.cpp
index 0445a856847be87661c7497f178da6e78ffc1a0a..acf8b05a5b561c7733a8bb487a9b6f01cee30fa4 100644
--- a/Source/platform/scroll/ScrollAnimator.cpp
+++ b/Source/platform/scroll/ScrollAnimator.cpp
@@ -60,16 +60,16 @@ ScrollResultOneDimensional ScrollAnimator::userScroll(ScrollbarOrientation orien
     float usedDelta = (newPos - currentPos) / step;
     currentPos = newPos;
 
-    notifyPositionChanged();
+    notifyPositionChanged(UserScroll);
 
     return ScrollResultOneDimensional(true, delta - usedDelta);
 }
 
-void ScrollAnimator::scrollToOffsetWithoutAnimation(const FloatPoint& offset)
+void ScrollAnimator::scrollToOffsetWithoutAnimation(const FloatPoint& offset, ScrollType scrollType)
 {
     m_currentPosX = offset.x();
     m_currentPosY = offset.y();
-    notifyPositionChanged();
+    notifyPositionChanged(scrollType);
 }
 
 ScrollResult ScrollAnimator::handleWheelEvent(const PlatformWheelEvent& e)
@@ -153,12 +153,12 @@ FloatPoint ScrollAnimator::currentPosition() const
     return FloatPoint(m_currentPosX, m_currentPosY);
 }
 
-void ScrollAnimator::notifyPositionChanged()
+void ScrollAnimator::notifyPositionChanged(ScrollType scrollType)
 {
     if (!m_scrollableArea->shouldUseIntegerScrollOffset())
-        m_scrollableArea->setScrollOffsetFromAnimation(DoublePoint(m_currentPosX, m_currentPosY));
+        m_scrollableArea->setScrollOffsetFromAnimation(DoublePoint(m_currentPosX, m_currentPosY), scrollType);
     else
-        m_scrollableArea->setScrollOffsetFromAnimation(IntPoint(m_currentPosX, m_currentPosY));
+        m_scrollableArea->setScrollOffsetFromAnimation(IntPoint(m_currentPosX, m_currentPosY), scrollType);
 }
 
 float ScrollAnimator::clampScrollPosition(ScrollbarOrientation orientation, float pos)