Remove GraphicsLayer::didScroll and directly call ScrollableArea::didScroll

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

Index: third_party/WebKit/Source/platform/scroll/ScrollableArea.cpp
diff --git a/third_party/WebKit/Source/platform/scroll/ScrollableArea.cpp b/third_party/WebKit/Source/platform/scroll/ScrollableArea.cpp
index 0e1681ef3de8de68557b632c4ba6cd0f38871993..b0a03cd8a8a1bbcf450bb1bfab2ac8676178243f 100644
--- a/third_party/WebKit/Source/platform/scroll/ScrollableArea.cpp
+++ b/third_party/WebKit/Source/platform/scroll/ScrollableArea.cpp
@@ -662,6 +662,12 @@ IntSize ScrollableArea::excludeScrollbars(const IntSize& size) const {
                  std::max(0, size.height() - horizontalScrollbarHeight()));
 }
 
+void ScrollableArea::didScroll(const gfx::ScrollOffset& offset) {
+  ScrollOffset newOffset = ScrollOffset(offset.x() - scrollOrigin().x(),
+                                        offset.y() - scrollOrigin().y());
+  setScrollOffset(newOffset, CompositorScroll);
+}
+
 DEFINE_TRACE(ScrollableArea) {
   visitor->trace(m_scrollAnimator);
   visitor->trace(m_programmaticScrollAnimator);