Ensure clean layout before calling TextIterator::rangeLength in editing code

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

 /*
  * Copyright (C) 2004, 2005, 2006, 2007 Apple Inc. All rights reserved.
  *
  * 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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 1684 matching lines @@
 
     Position p(visiblePosition.deepEquivalent());
     Document& document = *p.document();
     ShadowRoot* shadowRoot = p.anchorNode()->containingShadowRoot();
 
     if (shadowRoot)
         scope = shadowRoot;
     else
         scope = document.documentElement();
 
+    // TODO(xiaochengh): The use of updateStyleAndLayoutIgnorePendingStylesheets
+    // needs to be audited.  See http://crbug.com/590369 for more details.
+    document.updateStyleAndLayoutIgnorePendingStylesheets();

[yosin_UTC9, 2016/08/30 07:40:24]

I hope following patch will hoist this updateLayout to call sites of
indexForVisiblePosition()

[Xiaocheng, 2016/08/30 07:42:52]

Yeah, there will be such a patch.

+
+    // TODO(xiaochengh): We should use EphemeralRange here.
     Range* range = Range::create(document, Position::firstPositionInNode(scope), p.parentAnchoredEquivalent());
 
     return TextIterator::rangeLength(range->startPosition(), range->endPosition(), true);
 }
 
 EphemeralRange makeRange(const VisiblePosition &start, const VisiblePosition &end)
 {
     if (start.isNull() || end.isNull())
         return EphemeralRange();
 
@@ skipping 201 matching lines @@
             return InputType::DeleteWordBackward;
         if (granularity == LineBoundary)
             return InputType::DeleteLineBackward;
         return InputType::DeleteContentBackward;
     default:
         return InputType::None;
     }
 }
 
 } // namespace blink