Serializer: still install experimental globals when creating a snapshot.

test/cctest/test-serialize.cc

Index: test/cctest/test-serialize.cc
diff --git a/test/cctest/test-serialize.cc b/test/cctest/test-serialize.cc
index e16be9775c582d925ec5c6c6e43fe116c46672f4..49bc06433cbca78cb2dfac69cd327c35eac7f43f 100644
--- a/test/cctest/test-serialize.cc
+++ b/test/cctest/test-serialize.cc
@@ -709,7 +709,8 @@ TEST(PerIsolateSnapshotBlobs) {
   const char* source1 = "function f() { return 42; }";
   const char* source2 =
       "function f() { return g() * 2; }"
-      "function g() { return 43; }";
+      "function g() { return 43; }"
+      "/./.test('a')";
 
   v8::StartupData data1 = v8::V8::CreateSnapshotDataBlob(source1);
   v8::StartupData data2 = v8::V8::CreateSnapshotDataBlob(source2);