Move layout tree reconstruction code for Text nodes into new function

third_party/WebKit/Source/core/dom/Text.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights
  * reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
@@ skipping 378 matching lines @@
   CharacterData::attachLayoutTree(reattachContext);
 }
 
 void Text::recalcTextStyle(StyleRecalcChange change, Text* nextTextSibling) {
   if (LayoutTextItem layoutItem = LayoutTextItem(this->layoutObject())) {
     if (change != NoChange || needsStyleRecalc())
       layoutItem.setStyle(document().ensureStyleResolver().styleForText(this));
     if (needsStyleRecalc())
       layoutItem.setText(dataImpl());
     clearNeedsStyleRecalc();
-  } else if (needsStyleRecalc() || needsWhitespaceLayoutObject()) {
+  } else {
+    if (needsStyleRecalc()) {
+      setNeedsReattachLayoutTree();

[Bugs Nash, 2016/10/17 02:20:52]

probably don't need to implement this yet, not needed until 'The Reorg'

[nainar, 2016/10/17 16:57:31]

The flag setting is being done in the mirror patch here:
https://codereview.chromium.org/2398293003 and so should be done here. The next
patch (the reorg one) doesn't introduce the setting of the bits it just makes
sure that they are being set in the correct phases (style recalc and layout tree
construction).

+      clearNeedsStyleRecalc();

[Bugs Nash, 2016/10/17 02:20:52]

why is this being changed in this patch?

+    }
+    rebuildTextLayoutTree(nextTextSibling);
+  }
+}
+
+void Text::rebuildTextLayoutTree(Text* nextTextSibling) {
+  if (needsReattachLayoutTree() || needsWhitespaceLayoutObject()) {

[Bugs Nash, 2016/10/17 02:20:52]

this check doesn't belong in here, the method shouldn't be called if this
doesn't evaluate to true. you can change it to a DCHECK if you like, but leave
the 'if (needsStyleRecalc() || needsWhitespaceLayoutObject())' check in the
calling method

[nainar, 2016/10/17 16:57:31]

Seems like I misread your comment in the previous patch. Your comment intended
for this:

void Text::recalcTextStyle(StyleRecalcChange change, Text* nextTextSibling) {
  ...
  } else if (needsStyleRecalc() || needsWhitespaceLayoutObject()) {
    setNeedsReattachLayoutTree();
    rebuildTextLayoutTree(nextTextSibling);
  }
}

void Text::rebuildTextLayoutTree(Text* nextTextSibling) {
  reattachLayoutTree();
  if (this->layoutObject())
    reattachWhitespaceSiblingsIfNeeded(nextTextSibling);
  clearNeedsReattachLayoutTree();
}

Implemented this. Let me know if I still seem to be misunderstanding you. 

     reattachLayoutTree();
     if (this->layoutObject())
       reattachWhitespaceSiblingsIfNeeded(nextTextSibling);
     clearNeedsReattachLayoutTree();
   }
 }
 
 // If a whitespace node had no layoutObject and goes through a recalcStyle it
 // may need to create one if the parent style now has white-space: pre.
 bool Text::needsWhitespaceLayoutObject() {
@@ skipping 36 matching lines @@
 
 Text* Text::cloneWithData(const String& data) {
   return create(document(), data);
 }
 
 DEFINE_TRACE(Text) {
   CharacterData::trace(visitor);
 }
 
 }  // namespace blink