Ensure clean layout before calling plainText() (flat tree version)

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

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2012 Digia Plc. and/or its subsidiary(-ies)
  * Copyright (C) 2015 Google 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
@@ skipping 298 matching lines @@
     if (selectInputEventType == SelectInputEventType::Touch && result.image())
         adjustedHitTestResult.setNodeAndPosition(result.innerNode(), LayoutPoint(0, 0));
 
     const VisiblePositionInFlatTree& pos = visiblePositionOfHitTestResult(adjustedHitTestResult);
     if (pos.isNotNull()) {
         newSelection = VisibleSelectionInFlatTree(pos);
         newSelection.expandUsingGranularity(WordGranularity);
     }
 
     if (selectInputEventType == SelectInputEventType::Touch) {
+        if (pos.isNull())
+            return;
+
+        // TODO(xiaochengh): The use of updateStyleAndLayoutIgnorePendingStylesheets
+        // needs to be audited.  See http://crbug.com/590369 for more details.
+        pos.deepEquivalent().document()->updateStyleAndLayoutIgnorePendingStylesheets();

[yosin_UTC9, 2016/08/31 04:58:21]

There are only two call sites of selectClosestWordFromHitTestResult(),
updateLayout() should be there.
For SelectionController::handleGestureLongPress(), we don't need to call
updateLayout()

[Xiaocheng, 2016/09/02 05:37:24]

Done.
Is it because of the call to updateStyleAndLayoutTree()? What's its difference
with updateStyleAndLayout()?

+
         // If node doesn't have text except space, tab or line break, do not
         // select that 'empty' area.
         EphemeralRangeInFlatTree range(newSelection.start(), newSelection.end());
         const String& str = plainText(range, hasEditableStyle(*innerNode) ? TextIteratorEmitsObjectReplacementCharacter : TextIteratorDefaultBehavior);
         if (str.isEmpty() || str.simplifyWhiteSpace().containsOnlyWhitespace())
             return;
 
         if (newSelection.rootEditableElement() && pos.deepEquivalent() == VisiblePositionInFlatTree::lastPositionInNode(newSelection.rootEditableElement()).deepEquivalent())
             return;
     }
@@ skipping 343 matching lines @@
     return event.event().altKey() && event.isOverLink();
 }
 
 bool isExtendingSelection(const MouseEventWithHitTestResults& event)
 {
     bool isMouseDownOnLinkOrImage = event.isOverLink() || event.hitTestResult().image();
     return event.event().shiftKey() && !isMouseDownOnLinkOrImage;
 }
 
 } // namespace blink