[heap] Activate memory reducer on external memory activity.

src/isolate.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/isolate.h"
 
 #include <stdlib.h>
 
 #include <fstream>  // NOLINT(readability/streams)
 #include <sstream>
@@ skipping 2813 matching lines @@
   }
 
   CHECK_EQ(static_cast<int>(OFFSET_OF(Isolate, embedder_data_)),
            Internals::kIsolateEmbedderDataOffset);
   CHECK_EQ(static_cast<int>(OFFSET_OF(Isolate, heap_.roots_)),
            Internals::kIsolateRootsOffset);
   CHECK_EQ(static_cast<int>(OFFSET_OF(Isolate, heap_.external_memory_)),
            Internals::kExternalMemoryOffset);
   CHECK_EQ(static_cast<int>(OFFSET_OF(Isolate, heap_.external_memory_limit_)),
            Internals::kExternalMemoryLimitOffset);
+  CHECK_EQ(static_cast<int>(
+               OFFSET_OF(Isolate, heap_.external_memory_at_last_mark_compact_)),
+           Internals::kExternalMemoryAtLastMarkCompactOffset);
 
   time_millis_at_init_ = heap_.MonotonicallyIncreasingTimeInMs();
 
   {
     HandleScope scope(this);
     ast_string_constants_ = new AstStringConstants(this, heap()->HashSeed());
   }
 
   if (!serializer_enabled()) {
     // Ensure that all stubs which need to be generated ahead of time, but
@@ skipping 940 matching lines @@
   // Then check whether this scope intercepts.
   if ((flag & intercept_mask_)) {
     intercepted_flags_ |= flag;
     return true;
   }
   return false;
 }
 
 }  // namespace internal
 }  // namespace v8