Avoid allocating temporary ranges in connection with text and character iterators.

Source/core/editing/SurroundingText.cpp

 /*
  * Copyright (C) 2012 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 91 matching lines @@
 PassRefPtrWillBeRawPtr<Range> SurroundingText::rangeFromContentOffsets(unsigned startOffsetInContent, unsigned endOffsetInContent)
 {
     if (startOffsetInContent >= endOffsetInContent || endOffsetInContent > content().length())
         return nullptr;
 
     CharacterIterator iterator(m_contentRange.get());
 
     ASSERT(!iterator.atEnd());
     iterator.advance(startOffsetInContent);
 
-    ASSERT(iterator.range());
-    Position start = iterator.range()->startPosition();
+    Position start = iterator.startPosition();
 
     ASSERT(!iterator.atEnd());
     iterator.advance(endOffsetInContent - startOffsetInContent);
 
-    ASSERT(iterator.range());
-    Position end = iterator.range()->startPosition();
+    Position end = iterator.startPosition();
 
     ASSERT(start.document());
     return Range::create(*start.document(), start, end);
 }
 
 String SurroundingText::content() const
 {
     if (m_contentRange)
         return m_contentRange->text();
     return String();
 }
 
 unsigned SurroundingText::startOffsetInContent() const
 {
     return m_startOffsetInContent;
 }
 
 unsigned SurroundingText::endOffsetInContent() const
 {
     return m_endOffsetInContent;
 }
 
 } // namespace blink