From 6f3057ec7a612d63409a46ec0d18de0a93f67a46 Mon Sep 17 00:00:00 2001
From: Steven Orvell <sorvell@google.com>
Date: Tue, 13 Nov 2018 16:24:53 -0800
Subject: [PATCH] Ensure property values are always overridden by
 extendors/behaviors

---
 lib/legacy/class.html | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/lib/legacy/class.html b/lib/legacy/class.html
index 783322c236..e416c58314 100644
--- a/lib/legacy/class.html
+++ b/lib/legacy/class.html
@@ -156,6 +156,12 @@
     }
 
     function mergePropertyInfo(a, b) {
+      if ('value' in b) {
+        a.value = b.value;
+      // ensure property value is always overridden.
+      } else if ('value' in a) {
+        delete a.value;
+      }
       if (typeof b === 'function') {
         a.type = b;
         return;
@@ -163,9 +169,6 @@
       if ('type' in b) {
         a.type = b.type;
       }
-      if ('value' in b) {
-        a.value = b.value;
-      }
       // readOnly: cannot become false and takes on `computed` value
       a.readOnly = a.readOnly || Boolean(a.computed) || b.readOnly || Boolean(b.computed);
       // computed: first in wins