Backed out changeset 3b51e6804554 (bug 1747261) for causing xpcshell failures on test_E10SUtils_workers_remote_types.js. CLOSED TREE

modules/libpref/init/StaticPrefList.yaml

@@ -1427,6 +1427,14 @@
   value: true
   mirror: always
 
+# Temporary pref which makes certain ServiceWorkers be isolated in special
+# processes instead of within a the normal web/webIsolated process based on
+# the URI.  Entries are separated by commas
+- name: browser.tabs.remote.serviceWorkerIsolationList
+  type: String
+  value: ""
+  mirror: never
+
 # When this pref is enabled, opaque response is only allowed to enter the
 # content process if it's a response for media (audio, image, video), CSS, or
 # JavaScript.

toolkit/modules/E10SUtils.jsm

@@ -44,6 +44,16 @@ XPCOMUtils.defineLazyPreferenceGetter(
   "browser.tabs.remote.useCrossOriginOpenerPolicy",
   false
 );
+// Preference containing the list (comma separated) of origins that will
+// have ServiceWorkers isolated in special processes
+XPCOMUtils.defineLazyPreferenceGetter(
+  this,
+  "serviceWorkerIsolationList",
+  "browser.tabs.remote.serviceWorkerIsolationList",
+  "",
+  false,
+  val => val.split(",")
+);
 XPCOMUtils.defineLazyServiceGetter(
   this,
   "serializationHelper",
@@ -237,7 +247,10 @@ function validatedWebRemoteType(
 
     if (
       aIsWorker &&
-      aWorkerType === Ci.nsIE10SUtils.REMOTE_WORKER_TYPE_SERVICE
+      aWorkerType === Ci.nsIE10SUtils.REMOTE_WORKER_TYPE_SERVICE &&
+      serviceWorkerIsolationList.some(function(val) {
+        return targetPrincipal.siteOriginNoSuffix == val;
+      })
     ) {
       return `${SERVICEWORKER_REMOTE_TYPE}=${targetPrincipal.siteOrigin}`;
     }