Resolve references to "this" the same way as normal variables

src/scopeinfo.cc

Index: src/scopeinfo.cc
diff --git a/src/scopeinfo.cc b/src/scopeinfo.cc
index 99d4c38297890a22631e33a1aa1aa3cce1add481..993e2a5eaddd4884c0e2a442b21a9499e24548e6 100644
--- a/src/scopeinfo.cc
+++ b/src/scopeinfo.cc
@@ -307,7 +307,8 @@ bool ScopeInfo::LocalIsSynthetic(int var) {
   // with user declarations, the current temporaries like .generator_object and
   // .result start with a dot, so we can use that as a flag. It's a hack!
   Handle<String> name(LocalName(var));
-  return name->length() > 0 && name->Get(0) == '.';
+  return (name->length() > 0 && name->Get(0) == '.') ||
+         name->Equals(*GetIsolate()->factory()->this_string());
 }