Bug 1373449 Treat complete themes as legacy extensions r=rhelmer

MozReview-Commit-ID: I1AH07QSLNK

--HG--
extra : rebase_source : df30d3be7e46cef06a062e655aca184111c49dd4

toolkit/mozapps/extensions/internal/XPIProvider.jsm

@@ -265,6 +265,7 @@ const SIGNED_TYPES = new Set([
 const LEGACY_TYPES = new Set([
   "apiextension",
   "extension",
+  "theme",
 ]);
 
 const ALL_EXTERNAL_TYPES = new Set([

toolkit/mozapps/extensions/test/xpcshell/test_legacy.js

@@ -19,6 +19,13 @@ add_task(async function test_disable() {
       version: "1.0",
       type: 256,
     },
+    {
+      id: "theme@tests.mozilla.org",
+      name: "Theme",
+      version: "1.0",
+      type: 4,
+      internalName: "mytheme/1.0",
+    },
   ];
 
   let nonLegacy = [