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/CodeGen/CGVTables.cpp b/lib/CodeGen/CGVTables.cpp
index 96b3045..8a93344 100644
--- a/lib/CodeGen/CGVTables.cpp
+++ b/lib/CodeGen/CGVTables.cpp
@@ -63,7 +63,7 @@
   const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl());
 
   // Compute the mangled name.
-  llvm::SmallString<256> Name;
+  SmallString<256> Name;
   llvm::raw_svector_ostream Out(Name);
   if (const CXXDestructorDecl* DD = dyn_cast<CXXDestructorDecl>(MD))
     getCXXABI().getMangleContext().mangleCXXDtorThunk(DD, GD.getDtorType(),
@@ -622,7 +622,7 @@
   if (ShouldEmitVTableInThisTU(RD))
     CGM.DeferredVTables.push_back(RD);
 
-  llvm::SmallString<256> OutName;
+  SmallString<256> OutName;
   llvm::raw_svector_ostream Out(OutName);
   CGM.getCXXABI().getMangleContext().mangleCXXVTable(RD, Out);
   Out.flush();
@@ -677,7 +677,7 @@
   AddressPoints = VTLayout->getAddressPoints();
 
   // Get the mangled construction vtable name.
-  llvm::SmallString<256> OutName;
+  SmallString<256> OutName;
   llvm::raw_svector_ostream Out(OutName);
   CGM.getCXXABI().getMangleContext().
     mangleCXXCtorVTable(RD, Base.getBaseOffset().getQuantity(), Base.getBase(),