"Find" scrolling should be smoothly animated.

third_party/WebKit/Source/core/editing/Editor.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 1597 matching lines @@
 
 Range* Editor::FindStringAndScrollToVisible(const String& target,
                                             Range* previous_match,
                                             FindOptions options) {
   Range* next_match = FindRangeOfString(
       target, EphemeralRangeInFlatTree(previous_match), options);
   if (!next_match)
     return nullptr;
 
   Node* first_node = next_match->FirstNode();
+
   first_node->GetLayoutObject()->ScrollRectToVisible(
       LayoutRect(next_match->BoundingBox()),
       ScrollAlignment::kAlignCenterIfNeeded,
-      ScrollAlignment::kAlignCenterIfNeeded, kUserScroll);
+      ScrollAlignment::kAlignCenterIfNeeded, kProgrammaticScroll, true,
+      kScrollBehaviorSmooth);
+
   first_node->GetDocument().SetSequentialFocusNavigationStartingPoint(
       first_node);
 
   return next_match;
 }
 
 // TODO(yosin) We should return |EphemeralRange| rather than |Range|. We use
 // |Range| object for checking whether start and end position crossing shadow
 // boundaries, however we can do it without |Range| object.
 template <typename Strategy>
@@ skipping 209 matching lines @@
 
 DEFINE_TRACE(Editor) {
   visitor->Trace(frame_);
   visitor->Trace(last_edit_command_);
   visitor->Trace(undo_stack_);
   visitor->Trace(mark_);
   visitor->Trace(typing_style_);
 }
 
 }  // namespace blink