Tighten up Object.observe code to ASSERT that it never deals with globals

src/runtime.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <stdlib.h>
 #include <limits>
 
 #include "v8.h"
 
 #include "accessors.h"
@@ skipping 14865 matching lines @@
   return isolate->heap()->ToBoolean(obj->IsJSGlobalProxy());
 }
 
 
 RUNTIME_FUNCTION(Runtime_IsObserved) {
   SealHandleScope shs(isolate);
   ASSERT(args.length() == 1);
 
   if (!args[0]->IsJSReceiver()) return isolate->heap()->false_value();
   CONVERT_ARG_CHECKED(JSReceiver, obj, 0);
-  if (obj->IsJSGlobalProxy()) {
-    Object* proto = obj->GetPrototype();
-    if (proto->IsNull()) return isolate->heap()->false_value();
-    ASSERT(proto->IsJSGlobalObject());
-    obj = JSReceiver::cast(proto);
-  }
+  ASSERT(!obj->IsJSGlobalProxy() || !obj->map()->is_observed());
   return isolate->heap()->ToBoolean(obj->map()->is_observed());
 }
 
 
 RUNTIME_FUNCTION(Runtime_SetIsObserved) {
   HandleScope scope(isolate);
   ASSERT(args.length() == 1);
   CONVERT_ARG_HANDLE_CHECKED(JSReceiver, obj, 0);
-  if (obj->IsJSGlobalProxy()) {
-    Object* proto = obj->GetPrototype();
-    if (proto->IsNull()) return isolate->heap()->undefined_value();
-    ASSERT(proto->IsJSGlobalObject());
-    obj = handle(JSReceiver::cast(proto));
-  }
+  ASSERT(!obj->IsJSGlobalProxy());
   if (obj->IsJSProxy())
     return isolate->heap()->undefined_value();
 
   ASSERT(obj->IsJSObject());
   JSObject::SetObserved(Handle<JSObject>::cast(obj));
   return isolate->heap()->undefined_value();
 }
 
 
 RUNTIME_FUNCTION(Runtime_SetMicrotaskPending) {
@@ skipping 347 matching lines @@
   }
   return NULL;
 }
 
 
 const Runtime::Function* Runtime::FunctionForId(Runtime::FunctionId id) {
   return &(kIntrinsicFunctions[static_cast<int>(id)]);
 }
 
 } }  // namespace v8::internal