Move notification of isolate creation until after the ObjectStore is initialized.

runtime/vm/object.cc

Index: runtime/vm/object.cc
diff --git a/runtime/vm/object.cc b/runtime/vm/object.cc
index bbcb076cd129b99209ae0698eb5c3cde27ec67ba..2a0ae9218b7d29b9f00a491affb6701cc23ee9c6 100644
--- a/runtime/vm/object.cc
+++ b/runtime/vm/object.cc
@@ -18326,9 +18326,10 @@ RawOneByteString* ExternalOneByteString::EscapeSpecialCharacters(
 
 RawOneByteString* OneByteString::New(intptr_t len,
                                      Heap::Space space) {
-  ASSERT(Isolate::Current() == Dart::vm_isolate() ||
-         Isolate::Current()->object_store()->one_byte_string_class() !=
-         Class::null());
+  ASSERT((Isolate::Current() == Dart::vm_isolate()) ||
+         ((Isolate::Current()->object_store() != NULL) &&
+          (Isolate::Current()->object_store()->one_byte_string_class() !=
+           Class::null())));
   if (len < 0 || len > kMaxElements) {
     // This should be caught before we reach here.
     FATAL1("Fatal error in OneByteString::New: invalid len %" Pd "\n", len);