[Extensions] Finish freezing schema

extensions/renderer/resources/binding.js

Index: extensions/renderer/resources/binding.js
diff --git a/extensions/renderer/resources/binding.js b/extensions/renderer/resources/binding.js
index 0eef6cf9031ce0e3a5fdaa278a1b9f99a2009f94..c5690907f4008ba5ce7492dcac854fcbd7e6e495 100644
--- a/extensions/renderer/resources/binding.js
+++ b/extensions/renderer/resources/binding.js
@@ -484,7 +484,17 @@ Binding.prototype = {
           return;
         }
 
-        var value = propertyDef.value;
+        // |value| is eventually added to |m|, the exposed API. Make copies
+        // of everything from the schema. (The schema is also frozen, so as long
+        // as we don't make any modifications, shallow copies are fine.)
+        var value;
+        if ($Array.isArray(propertyDef.value))
+          value = $Array.slice(propertyDef.value);
+        else if (typeof propertyDef.value === 'object')
+          value = $Object.assign({}, propertyDef.value);
+        else
+          value = propertyDef.value;
+
         if (value) {
           // Values may just have raw types as defined in the JSON, such
           // as "WINDOW_ID_NONE": { "value": -1 }. We handle this here.