[rab/gsab] Fix missing assignment in BackingStore::Reallocate

See https://github.com/nodejs/node/pull/39945

Bug: v8:11111
Change-Id: I7271a907bf036c18a014b2a13ff5746db622456a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3141581Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Marja Hölttä <marja@chromium.org>
Cr-Commit-Position: refs/heads/main@{#76670}

src/objects/backing-store.cc

@@ -796,7 +796,7 @@ std::unique_ptr<BackingStore> BackingStore::EmptyBackingStore(
 
 bool BackingStore::Reallocate(Isolate* isolate, size_t new_byte_length) {
   CHECK(!is_wasm_memory_ && !custom_deleter_ && !globally_registered_ &&
-        free_on_destruct_);
+        free_on_destruct_ && !is_resizable_);
   auto allocator = get_v8_api_array_buffer_allocator();
   CHECK_EQ(isolate->array_buffer_allocator(), allocator);
   CHECK_EQ(byte_length_, byte_capacity_);
@@ -806,6 +806,7 @@ bool BackingStore::Reallocate(Isolate* isolate, size_t new_byte_length) {
   buffer_start_ = new_start;
   byte_capacity_ = new_byte_length;
   byte_length_ = new_byte_length;
+  max_byte_length_ = new_byte_length;
   return true;
 }