Store Object.observe state per-isolate rather than per-context

src/objects-inl.h

Index: src/objects-inl.h
diff --git a/src/objects-inl.h b/src/objects-inl.h
index bbd1a09a32039b48fb0cd0e87d4164ddc98cb0aa..17e42115e370a4a2d1ea823e0792bb4898eb2d3f 100644
--- a/src/objects-inl.h
+++ b/src/objects-inl.h
@@ -726,6 +726,12 @@ bool Object::IsMapCache() {
 }
 
 
+bool Object::IsObjectHashTable() {
+  // TODO: Is this sufficient?

[rossberg, 2012/11/06 12:27:09]

Yeah, I don't think it's worth introducing the extra (sub)type in the heap_types
list when you cannot check for it anyways.

[adamk, 2012/11/06 12:59:13]

Okay, I've removed this and completely redone the functions in runtime.cc to
minimize the checks they do (also changed the safe ones to not use handles). Let
me know if I went overboard there.

+  return IsHashTable();
+}
+
+
 bool Object::IsPrimitive() {
   return IsOddball() || IsNumber() || IsString();
 }