Restore a collapsed trailing space of text used for line break

third_party/WebKit/Source/core/layout/line/BreakingContextInlineHeaders.h

 /*
  * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2003, 2004, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All right reserved.
  * Copyright (C) 2010 Google Inc. All rights reserved.
  * Copyright (C) 2013 Adobe Systems Incorporated.
  *
  * 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 1141 matching lines @@
     }
 
     ASSERT_WITH_SECURITY_IMPLICATION(m_currentStyle->refCount() > 0);
     if (checkForBreak && !m_width.fitsOnLine()) {
         // if we have floats, try to get below them.
         if (m_currentCharacterIsSpace && !m_ignoringSpaces && m_currentStyle->collapseWhiteSpace())
             m_trailingObjects.clear();
 
         if (m_width.committedWidth()) {
             m_atEnd = true;
+            // When the leading or trailing space of text is collapsed and a line break is inserted instead of it,
+            // we need to restore the space while the text is copied(ctrl+c). See http://crbug.com/318925
+            if (m_lastObject && m_lastObject.isText() && m_current.getLineLayoutItem().isText()) {
+                LineLayoutText lastLayoutText(m_lastObject);
+                if (lastLayoutText.text().endsWith(' '))
+                    lastLayoutText.setNeedToRestoreCollapsedSpace(true);
+            }
             return;
         }
 
         m_width.fitBelowFloats(m_lineInfo.isFirstLine());
 
         // |width| may have been adjusted because we got shoved down past a float (thus
         // giving us more room), so we need to retest, and only jump to
         // the end label if we still don't fit on the line. -dwh
         if (!m_width.fitsOnLine()) {
             m_atEnd = true;
@@ skipping 23 matching lines @@
 
     if (style.getTextIndentType() == TextIndentHanging)
         indentText = indentText == IndentText ? DoNotIndentText : IndentText;
 
     return indentText;
 }
 
 } // namespace blink
 
 #endif // BreakingContextInlineHeaders_h