[serializer] ensure that immortal immovable roots are correctly deserialized.

test/cctest/test-serialize.cc

 // Copyright 2007-2010 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 836 matching lines @@
     CHECK(IsCompiled("f"));
     CHECK(IsCompiled("Math.sin"));
     CHECK(!IsCompiled("g"));
     CHECK(!IsCompiled("Math.cos"));
     CHECK(!IsCompiled("Math.tan"));
     CHECK_EQ(5, CompileRun("a")->Int32Value(context).FromJust());
   }
   isolate->Dispose();
 }
 
+TEST(CustomSnapshotDataBlobImmortalImmovableRoots) {
+  DisableTurbofan();
+  // Flood the startup snapshot with shared function infos. If they are
+  // serialized before the immortal immovable root, the root will no longer end
+  // up on the first page.
+  Vector<const uint8_t> source =
+      ConstructSource(STATIC_CHAR_VECTOR("var a = [];"),
+                      STATIC_CHAR_VECTOR("a.push(function() {return 7});"),
+                      STATIC_CHAR_VECTOR("\0"), 10000);
+
+  v8::StartupData data = v8::V8::CreateSnapshotDataBlob(
+      reinterpret_cast<const char*>(source.start()));
+
+  v8::Isolate::CreateParams params;
+  params.snapshot_blob = &data;
+  params.array_buffer_allocator = CcTest::array_buffer_allocator();
+
+  v8::Isolate* isolate = v8::Isolate::New(params);
+  {
+    v8::Isolate::Scope i_scope(isolate);
+    v8::HandleScope h_scope(isolate);
+    v8::Local<v8::Context> context = v8::Context::New(isolate);
+    delete[] data.data;  // We can dispose of the snapshot blob now.
+    v8::Context::Scope c_scope(context);
+    CHECK_EQ(7, CompileRun("a[0]()")->Int32Value(context).FromJust());
+  }
+  isolate->Dispose();
+  source.Dispose();
+}
+
 TEST(TestThatAlwaysSucceeds) {
 }
 
 
 TEST(TestThatAlwaysFails) {
   bool ArtificialFailure = false;
   CHECK(ArtificialFailure);
 }
 
 
@@ skipping 936 matching lines @@
   delete script_data;
 }
 
 
 TEST(SerializationMemoryStats) {
   FLAG_profile_deserialization = true;
   FLAG_always_opt = false;
   v8::StartupData blob = v8::V8::CreateSnapshotDataBlob();
   delete[] blob.data;
 }