Removed main-thread one dimensional scrolling paths.

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 e48362a77bcc9b7c7ba798ff3c39d76bd24eb5c7..ee37d7d5c813e130848f0fe1dba8c23834cb4c91 100644
--- a/third_party/WebKit/Source/platform/scroll/Scrollbar.cpp
+++ b/third_party/WebKit/Source/platform/scroll/Scrollbar.cpp
@@ -202,7 +202,7 @@ void Scrollbar::autoscrollPressedPart(double delay)
     }
 
     // Handle the arrows and track.
-    if (m_scrollableArea && m_scrollableArea->userScroll(pressedPartScrollDirectionPhysical(), pressedPartScrollGranularity()).didScroll)
+    if (m_scrollableArea && m_scrollableArea->userScroll(pressedPartScrollGranularity(), toScrollDelta(pressedPartScrollDirectionPhysical(), 1)).didScroll())
         startTimerIfNeeded(delay);
 }
 
@@ -353,7 +353,7 @@ bool Scrollbar::gestureEvent(const PlatformGestureEvent& evt)
         return false;
     case PlatformEvent::GestureTap: {
         if (m_pressedPart != ThumbPart && m_pressedPart != NoPart && m_scrollableArea
-            && m_scrollableArea->userScroll(pressedPartScrollDirectionPhysical(), pressedPartScrollGranularity()).didScroll) {
+            && m_scrollableArea->userScroll(pressedPartScrollGranularity(), toScrollDelta(pressedPartScrollDirectionPhysical(), 1)).didScroll()) {
             return true;
         }
         m_scrollPos = 0;