Revert "[WebRequest] Remove AddonManagerPermissions leftovers"

dom/bindings/Bindings.conf

@@ -53,6 +53,11 @@ DOMInterfaces = {
     'concrete': False
 },
 
+'AddonManagerPermissions': {
+    'wrapperCache': False,
+    'concrete': False
+},
+
 'AnimationEffectReadOnly': {
     'concrete': False
 },

toolkit/modules/addons/.eslintrc.js

@@ -8,6 +8,7 @@ module.exports = { // eslint-disable-line no-undef
     "addMessageListener": false,
     "removeEventListener": false,
     "sendAsyncMessage": false,
+    "AddonManagerPermissions": false,
 
     "initialProcessData": true,
   },

toolkit/modules/addons/WebRequest.jsm

@@ -720,7 +720,11 @@ HttpObserverManager = {
         try {
           let result = callback(data);
 
-          if (result && typeof result === "object" && opts.blocking) {
+          if (result && typeof result === "object" && opts.blocking
+              && !AddonManagerPermissions.isHostPermitted(uri.host)
+              && (!loadInfo || !loadInfo.loadingPrincipal
+                  || !loadInfo.loadingPrincipal.URI
+                  || !AddonManagerPermissions.isHostPermitted(loadInfo.loadingPrincipal.URI.host))) {
             handlerResults.push({opts, result});
           }
         } catch (e) {