Rename ScrollType helper and combine some redundant checks.

third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple Inc. All rights
  * reserved.
  *
  * Portions are Copyright (C) 1998 Netscape Communications Corporation.
  *
  * Other contributors:
  *   Robert O'Callahan <roc+@cs.cmu.edu>
  *   David Baron <dbaron@fas.harvard.edu>
  *   Christian Biesinger <cbiesinger@gmail.com>
@@ skipping 453 matching lines @@
     cache->HandleScrollPositionChanged(&Box());
   Box().View()->ClearHitTestCache();
 
   // Inform the FrameLoader of the new scroll position, so it can be restored
   // when navigating back.
   if (Layer()->IsRootLayer()) {
     frame_view->GetFrame().Loader().SaveScrollState();
     frame_view->DidChangeScrollOffset();
   }
 
-  if (ScrollTypeClearsFragmentAnchor(scroll_type))
+  if (IsExplicitScrollType(scroll_type)) {
     frame_view->ClearFragmentAnchor();
-
-  // Clear the scroll anchor, unless it is the reason for this scroll.
-  if (RuntimeEnabledFeatures::scrollAnchoringEnabled() &&
-      scroll_type != kAnchoringScroll && scroll_type != kClampingScroll)
-    GetScrollAnchor()->Clear();
+    if (RuntimeEnabledFeatures::scrollAnchoringEnabled())
+      GetScrollAnchor()->Clear();
+  }
 }
 
 IntSize PaintLayerScrollableArea::ScrollOffsetInt() const {
   return FlooredIntSize(scroll_offset_);
 }
 
 ScrollOffset PaintLayerScrollableArea::GetScrollOffset() const {
   return scroll_offset_;
 }
 
@@ skipping 1633 matching lines @@
 
 void PaintLayerScrollableArea::DelayScrollOffsetClampScope::
     ClampScrollableAreas() {
   for (auto& scrollable_area : *needs_clamp_)
     scrollable_area->ClampScrollOffsetAfterOverflowChange();
   delete needs_clamp_;
   needs_clamp_ = nullptr;
 }
 
 }  // namespace blink