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/AST/ItaniumMangle.cpp b/lib/AST/ItaniumMangle.cpp
index 5dbcf22..9c697ed 100644
--- a/lib/AST/ItaniumMangle.cpp
+++ b/lib/AST/ItaniumMangle.cpp
@@ -1083,7 +1083,7 @@
     // Mangle it as a source name in the form
     // [n] $_<id>
     // where n is the length of the string.
-    llvm::SmallString<8> Str;
+    SmallString<8> Str;
     Str += "$_";
     Str += llvm::utostr(AnonStructId);
 
@@ -1291,7 +1291,7 @@
 
   if (const BlockDecl *Block = dyn_cast<BlockDecl>(DC)) {
     manglePrefix(DC->getParent(), NoFunction);    
-    llvm::SmallString<64> Name;
+    SmallString<64> Name;
     llvm::raw_svector_ostream NameStream(Name);
     Context.mangleBlock(Block, NameStream);
     NameStream.flush();
@@ -1555,7 +1555,7 @@
     // 
     // where <address-space-number> is a source name consisting of 'AS' 
     // followed by the address space <number>.
-    llvm::SmallString<64> ASString;
+    SmallString<64> ASString;
     ASString = "AS" + llvm::utostr_32(Quals.getAddressSpace());
     Out << 'U' << ASString.size() << ASString;
   }