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

test/mjsunit/debug-scopes.js

Index: test/mjsunit/debug-scopes.js
diff --git a/test/mjsunit/debug-scopes.js b/test/mjsunit/debug-scopes.js
index ad137de205f80dea027b2a78d2191fab56342dc7..1e1e22aa6bf5ccb45c4c149c60261239575f5021 100644
--- a/test/mjsunit/debug-scopes.js
+++ b/test/mjsunit/debug-scopes.js
@@ -167,6 +167,10 @@ function CheckScopeContent(content, number, exec_state) {
   if (!scope.scopeObject().property('arguments').isUndefined()) {
     scope_size--;
   }
+  // Ditto for 'this'.
+  if (!scope.scopeObject().property('this').isUndefined()) {
+    scope_size--;
+  }
   // Skip property with empty name.
   if (!scope.scopeObject().property('').isUndefined()) {
     scope_size--;