A64: Synchronize with r18084.

src/property-details.h

Index: src/property-details.h
diff --git a/src/property-details.h b/src/property-details.h
index 36f140681fe8d5ab916bd3bb1ccfa1b8ad68bd06..617e9b2af76ff3e9aa6ab9a273c1783866bd4b3a 100644
--- a/src/property-details.h
+++ b/src/property-details.h
@@ -131,6 +131,10 @@ class Representation {
   }
 
   bool is_more_general_than(const Representation& other) const {
+    if (kind_ == kExternal && other.kind_ == kNone) return true;
+    if (kind_ == kExternal && other.kind_ == kExternal) return false;
+    if (kind_ == kNone && other.kind_ == kExternal) return false;
+
     ASSERT(kind_ != kExternal);
     ASSERT(other.kind_ != kExternal);
     if (IsHeapObject()) return other.IsDouble() || other.IsNone();