Make stray 'return' an early error

src/parser.h

Index: src/parser.h
diff --git a/src/parser.h b/src/parser.h
index 6a164c7f6f0a7c3be43abd29a41f30055071f805..cf7d2a5905b1e3f12d472b4e9033275c394ac142 100644
--- a/src/parser.h
+++ b/src/parser.h
@@ -538,8 +538,7 @@ class ParserTraits {
 
   // Generate AST node that throws a TypeError with the given
   // type. Both arguments must be non-null (in the handle sense).
-  Expression* NewThrowTypeError(
-      const char* type, Handle<Object> arg1, Handle<Object> arg2, int pos);
+  Expression* NewThrowTypeError(const char* type, Handle<Object> arg, int pos);
 
   // Generic AST generator for throwing errors from compiled code.
   Expression* NewThrowError(