Add kGCCallbackFlagCollectAllExternalMemory

src/heap/heap.cc

Index: src/heap/heap.cc
diff --git a/src/heap/heap.cc b/src/heap/heap.cc
index 0d753e2227654db5244900aeb958802cf242201e..de142fbdb774a4bf1f74769d334a376d5be340c7 100644
--- a/src/heap/heap.cc
+++ b/src/heap/heap.cc
@@ -903,13 +903,13 @@ void Heap::CollectAllAvailableGarbage(const char* gc_reason) {
 
 void Heap::ReportExternalMemoryPressure(const char* gc_reason) {
   if (incremental_marking()->IsStopped()) {
+    v8::GCCallbackFlags flags = static_cast<v8::GCCallbackFlags>(
+        kGCCallbackFlagSynchronousPhantomCallbackProcessing |
+        kGCCallbackFlagCollectAllExternalMemory);
     if (incremental_marking()->CanBeActivated()) {
-      StartIncrementalMarking(
-          i::Heap::kNoGCFlags,
-          kGCCallbackFlagSynchronousPhantomCallbackProcessing, gc_reason);
+      StartIncrementalMarking(i::Heap::kNoGCFlags, flags, gc_reason);
     } else {
-      CollectAllGarbage(i::Heap::kNoGCFlags, gc_reason,
-                        kGCCallbackFlagSynchronousPhantomCallbackProcessing);
+      CollectAllGarbage(i::Heap::kNoGCFlags, gc_reason, flags);
     }
   } else {
     // Incremental marking is turned on an has already been started.