Clamping shouldn't clear the fragment anchor.

third_party/WebKit/Source/platform/scroll/ScrollTypes.h

Index: third_party/WebKit/Source/platform/scroll/ScrollTypes.h
diff --git a/third_party/WebKit/Source/platform/scroll/ScrollTypes.h b/third_party/WebKit/Source/platform/scroll/ScrollTypes.h
index e598cc66a9d9a7eb0bec880b20cfddaf9ea34fbe..e8e79724f16665408e5998372a906d3eb1667db9 100644
--- a/third_party/WebKit/Source/platform/scroll/ScrollTypes.h
+++ b/third_party/WebKit/Source/platform/scroll/ScrollTypes.h
@@ -64,6 +64,11 @@ enum ScrollType {
   AnchoringScroll
 };
 
+inline bool scrollTypeClearsFragmentAnchor(ScrollType scrollType) {
+  return scrollType == UserScroll || scrollType == ProgrammaticScroll ||
+         scrollType == CompositorScroll;
+}
+
 // Convert logical scroll direction to physical. Physical scroll directions are
 // unaffected.
 inline ScrollDirectionPhysical toPhysicalDirection(ScrollDirection direction,