Fix CurrentMapForDeprecated() to return MaybeHandle instead of a null handle.

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index 70d441067203ebdbbfa60a7e62c35e728e2a369a..3da37b0ba6d7a8f0f97b02dfbbcfd4ad81b23543 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -2294,8 +2294,8 @@ class JSObject: public JSReceiver {
   static void MigrateInstance(Handle<JSObject> instance);
 
   // Migrates the given object only if the target map is already available,
-  // or returns an empty handle if such a map is not yet available.
-  static Handle<Object> TryMigrateInstance(Handle<JSObject> instance);
+  // or returns false if such a map is not yet available.
+  static bool TryMigrateInstance(Handle<JSObject> instance);
 
   // Retrieve a value in a normalized object given a lookup result.
   // Handles the special representation of JS global objects.
@@ -6444,9 +6444,11 @@ class Map: public HeapObject {
   // is found by re-transitioning from the root of the transition tree using the
   // descriptor array of the map. Returns NULL if no updated map is found.
   // This method also applies any pending migrations along the prototype chain.
-  static Handle<Map> CurrentMapForDeprecated(Handle<Map> map);
+  static MaybeHandle<Map> CurrentMapForDeprecated(Handle<Map> map)
+      V8_WARN_UNUSED_RESULT;
   // Same as above, but does not touch the prototype chain.
-  static Handle<Map> CurrentMapForDeprecatedInternal(Handle<Map> map);
+  static MaybeHandle<Map> CurrentMapForDeprecatedInternal(Handle<Map> map)
+      V8_WARN_UNUSED_RESULT;
 
   static Handle<Map> CopyDropDescriptors(Handle<Map> map);
   static Handle<Map> CopyInsertDescriptor(Handle<Map> map,