1. Write the backing data array of a GrowableObjectArray as a reference

runtime/vm/object.h

Index: runtime/vm/object.h
diff --git a/runtime/vm/object.h b/runtime/vm/object.h
index 28926e56734267fd11f6a653c2fbda04450b7a21..f01021c318fd108757728156a4669024fb61f485 100644
--- a/runtime/vm/object.h
+++ b/runtime/vm/object.h
@@ -180,7 +180,8 @@ class Symbols;
   static Raw##object* ReadFrom(SnapshotReader* reader,                         \
                                intptr_t object_id,                             \
                                intptr_t tags,                                  \
-                               Snapshot::Kind);                                \
+                               Snapshot::Kind,                                 \
+                               bool as_reference);                             \
   friend class SnapshotReader;                                                 \
 
 #define OBJECT_IMPLEMENTATION(object, super)                                   \
@@ -6391,7 +6392,8 @@ class OneByteString : public AllStatic {
   static RawOneByteString* ReadFrom(SnapshotReader* reader,
                                     intptr_t object_id,
                                     intptr_t tags,
-                                    Snapshot::Kind kind);
+                                    Snapshot::Kind kind,
+                                    bool as_reference);
 
   friend class Class;
   friend class String;
@@ -6506,7 +6508,8 @@ class TwoByteString : public AllStatic {
   static RawTwoByteString* ReadFrom(SnapshotReader* reader,
                                     intptr_t object_id,
                                     intptr_t tags,
-                                    Snapshot::Kind kind);
+                                    Snapshot::Kind kind,
+                                    bool as_reference);
 
   friend class Class;
   friend class String;
@@ -6584,7 +6587,8 @@ class ExternalOneByteString : public AllStatic {
   static RawExternalOneByteString* ReadFrom(SnapshotReader* reader,
                                             intptr_t object_id,
                                             intptr_t tags,
-                                            Snapshot::Kind kind);
+                                            Snapshot::Kind kind,
+                                            bool as_reference);
 
   static intptr_t NextFieldOffset() {
     // Indicates this class cannot be extended by dart code.
@@ -6663,7 +6667,8 @@ class ExternalTwoByteString : public AllStatic {
   static RawExternalTwoByteString* ReadFrom(SnapshotReader* reader,
                                             intptr_t object_id,
                                             intptr_t tags,
-                                            Snapshot::Kind kind);
+                                            Snapshot::Kind kind,
+                                            bool as_reference);
 
   static intptr_t NextFieldOffset() {
     // Indicates this class cannot be extended by dart code.
@@ -6835,7 +6840,8 @@ class ImmutableArray : public AllStatic {
   static RawImmutableArray* ReadFrom(SnapshotReader* reader,
                                      intptr_t object_id,
                                      intptr_t tags,
-                                     Snapshot::Kind kind);
+                                     Snapshot::Kind kind,
+                                     bool as_reference);
 
   static const ClassId kClassId = kImmutableArrayCid;