Bug 1803158 - convert session restore consumers to reference the sys.mjs files instead, r=webdriver-reviewers,perftest-reviewers,extension-reviewers,credential-management-reviewers,Standard8,sgalich,whimboo,sparky,willdurand

Differential Revision: https://phabricator.services.mozilla.com/D163350

browser/components/migration/FirefoxProfileMigrator.sys.mjs

@@ -22,12 +22,8 @@ ChromeUtils.defineESModuleGetters(lazy, {
   FileUtils: "resource://gre/modules/FileUtils.sys.mjs",
   PlacesBackups: "resource://gre/modules/PlacesBackups.sys.mjs",
   ProfileAge: "resource://gre/modules/ProfileAge.sys.mjs",
+  SessionMigration: "resource:///modules/sessionstore/SessionMigration.sys.mjs",
 });
-ChromeUtils.defineModuleGetter(
-  lazy,
-  "SessionMigration",
-  "resource:///modules/sessionstore/SessionMigration.jsm"
-);
 
 export function FirefoxProfileMigrator() {
   this.wrappedJSObject = this; // for testing...

browser/components/migration/tests/marionette/test_refresh_firefox.py

@@ -180,7 +180,7 @@ class TestFirefoxRefresh(MarionetteTestCase):
           const COMPLETE_STATE = Ci.nsIWebProgressListener.STATE_STOP +
                                  Ci.nsIWebProgressListener.STATE_IS_NETWORK;
           let { TabStateFlusher } = ChromeUtils.import(
-            "resource:///modules/sessionstore/TabStateFlusher.jsm"
+            "resource:///modules/sessionstore/TabStateFlusher.sys.mjs"
           );
           let expectedURLs = Array.from(arguments[0])
           gBrowser.addTabsProgressListener({