Fix some problems reported by clang static analyzer

Source/core/editing/ApplyStyleCommand.cpp

 /*
  * Copyright (C) 2005, 2006, 2008, 2009 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 1249 matching lines @@
     if (startOffset)
         return false;
 
     if (isAtomicNode(startNode)) {
         // note: prior siblings could be unrendered elements. it's silly to miss the
         // merge opportunity just for that.
         if (startNode->previousSibling())
             return false;
 
         startNode = startNode->parentNode();
-        startOffset = 0;
     }
 
     if (!startNode->isElementNode())
         return false;
 
     Node* previousSibling = startNode->previousSibling();
 
     if (previousSibling && areIdenticalElements(startNode, previousSibling)) {
         Element* previousElement = toElement(previousSibling);
         Element* element = toElement(startNode);
@@ skipping 262 matching lines @@
         String textToMove = nextText->data();
         insertTextIntoNode(childText, childText->length(), textToMove);
         removeNode(next);
         // don't move child node pointer. it may want to merge with more text nodes.
     }
 
     updateStartEnd(newStart, newEnd);
 }
 
 }