Basic: import SmallString<> into clang namespace

(I was going to fix the TODO about DenseMap too, but
that would break self-host right now. See PR11922.)

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@149799 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/StaticAnalyzer/Checkers/StackAddrEscapeChecker.cpp b/lib/StaticAnalyzer/Checkers/StackAddrEscapeChecker.cpp
index 3046f96..d071ef8 100644
--- a/lib/StaticAnalyzer/Checkers/StackAddrEscapeChecker.cpp
+++ b/lib/StaticAnalyzer/Checkers/StackAddrEscapeChecker.cpp
@@ -100,7 +100,7 @@
                  new BuiltinBug("Return of address to stack-allocated memory"));
 
   // Generate a report for this bug.
-  llvm::SmallString<512> buf;
+  SmallString<512> buf;
   llvm::raw_svector_ostream os(buf);
   SourceRange range = GenName(os, R, C.getSourceManager());
   os << " returned to caller";
@@ -201,7 +201,7 @@
   
   for (unsigned i = 0, e = cb.V.size(); i != e; ++i) {
     // Generate a report for this bug.
-    llvm::SmallString<512> buf;
+    SmallString<512> buf;
     llvm::raw_svector_ostream os(buf);
     SourceRange range = GenName(os, cb.V[i].second,
                                 Ctx.getSourceManager());