Add Isolate parameter to Persistent class.

src/mksnapshot.cc

Index: src/mksnapshot.cc
diff --git a/src/mksnapshot.cc b/src/mksnapshot.cc
index d7775517b7d26b20bb37fc8d109bacb212c878f5..a3665e969df2db02ddcedf2de3e06a2aa4797efa 100644
--- a/src/mksnapshot.cc
+++ b/src/mksnapshot.cc
@@ -384,7 +384,7 @@ int main(int argc, char** argv) {
   // context even after we have disposed of the context.
   HEAP->CollectAllGarbage(i::Heap::kNoGCFlags, "mksnapshot");
   i::Object* raw_context = *(v8::Utils::OpenHandle(*context));
-  context.Dispose();
+  context.Dispose(context->GetIsolate());
   CppByteSink sink(argv[1]);
   // This results in a somewhat smaller snapshot, probably because it gets rid
   // of some things that are cached between garbage collections.