PlaygroundTransform: Increase TmpNameIndex after allocating a temporary variable.

Author: adrian-prantl

lib/Sema/PlaygroundTransform.cpp

@@ -744,7 +744,7 @@ class Instrumenter : InstrumenterBase {
   std::pair<PatternBindingDecl *, VarDecl *>
   buildPatternAndVariable(Expr *InitExpr) {
     SmallString<16> NameBuf;
-    (Twine("tmp") + Twine(TmpNameIndex)).toVector(NameBuf);
+    (Twine("tmp") + Twine(TmpNameIndex++)).toVector(NameBuf);
 
     Expr *MaybeLoadInitExpr = nullptr;