Simply v8::Isolate::New to test if snapshot blob needed
Simply v8::Isolate::New to test if snapshot blob needed

The test on internal symbols seems too fragile, e.g. with V8
version 4.5.90 it is false positive.

phpv8/v8js,stesie/v8js,stesie/v8js,preillyme/v8js,preillyme/v8js,phpv8/v8js,phpv8/v8js,stesie/v8js,preillyme/v8js,preillyme/v8js,stesie/v8js