Fix clang-format CLion integration bug.

CLion's Sax parser threw this error:

Failed to parse clang-format XML replacements. Input: <?xml version='1.0'?>
<replacements xml:space='preserve' incomplete_format='true' line=89>
[...]
[org.xml.sax.SAXParseException; lineNumber: 2; columnNumber: 66; Open quote is expected for attribute "line" associated with an  element type  "replacements".]

Patch by Justine Tunney (jart@google.com)!

llvm-svn: 317205