Revert "Reland: Make ScrollbarThemeAura selectively invalidate scrollbar parts."

third_party/WebKit/Source/core/frame/FrameView.cpp

Index: third_party/WebKit/Source/core/frame/FrameView.cpp
diff --git a/third_party/WebKit/Source/core/frame/FrameView.cpp b/third_party/WebKit/Source/core/frame/FrameView.cpp
index fa47e6bb237fad9ef3e707449e9ce002b23bbc0f..e53c53f5c6359677dff739ebd0fded483f28fedb 100644
--- a/third_party/WebKit/Source/core/frame/FrameView.cpp
+++ b/third_party/WebKit/Source/core/frame/FrameView.cpp
@@ -2084,8 +2084,10 @@ void FrameView::scrollTo(const DoublePoint& newPosition)
 
 void FrameView::invalidatePaintForTickmarks()
 {
-    if (Scrollbar* scrollbar = verticalScrollbar())
-        scrollbar->setNeedsPaintInvalidation(static_cast<ScrollbarPart>(~ThumbPart));
+    if (Scrollbar* scrollbar = verticalScrollbar()) {
+        scrollbar->setTrackNeedsRepaint(true);
+        setScrollbarNeedsPaintInvalidation(VerticalScrollbar);
+    }
 }
 
 void FrameView::getTickmarks(Vector<IntRect>& tickmarks) const