Reduce the number of implicit StringRef->std::string conversions by threading StringRef through more APIs.

No functionality change intended.

llvm-svn: 260815

clang/lib/Index/CommentToXML.cpp

@@ -592,9 +592,8 @@ void getSourceTextOfDeclaration(const DeclInfo *ThisDecl,
 
 void CommentASTToXMLConverter::formatTextOfDeclaration(
     const DeclInfo *DI, SmallString<128> &Declaration) {
-  // FIXME. formatting API expects null terminated input string.
-  // There might be more efficient way of doing this.
-  std::string StringDecl = Declaration.str();
+  // Formatting API expects null terminated input string.
+  StringRef StringDecl(Declaration.c_str(), Declaration.size());
 
   // Formatter specific code.
   // Form a unique in memory buffer name.