Bug 1708256 - Remove the browser-child.js frame script, r=mconley,perftest-reviewers

Differential Revision: https://phabricator.services.mozilla.com/D114790

testing/talos/talos/tests/cpstartup/extension/api.js

@@ -22,7 +22,7 @@ ChromeUtils.defineModuleGetter(
 );
 
 const PREALLOCATED_PREF = "dom.ipc.processPrelaunch.enabled";
-const MESSAGES = ["CPStartup:Go", "Content:BrowserChildReady"];
+const MESSAGES = ["CPStartup:Go", "CPStartup:BrowserChildReady"];
 let domainID = 1;
 
 /* global ExtensionAPI */
@@ -70,7 +70,7 @@ this.cpstartup = class extends ExtensionAPI {
         break;
       }
 
-      case "Content:BrowserChildReady": {
+      case "CPStartup:BrowserChildReady": {
         // Content has reported that it's ready to process an URL.
         if (!this.readyCallback) {
           throw new Error(

testing/talos/talos/tests/cpstartup/extension/framescript.js

@@ -1,4 +1,11 @@
 (function() {
+  const { Services } = ChromeUtils.import(
+    "resource://gre/modules/Services.jsm"
+  );
+  sendAsyncMessage("CPStartup:BrowserChildReady", {
+    time: Services.telemetry.msSystemNow(),
+  });
+
   addEventListener(
     "CPStartup:Ping",
     e => {

toolkit/content/browser-child.js

@@ -1,13 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-/* eslint-env mozilla/frame-script */
-
-const { Services } = ChromeUtils.import("resource://gre/modules/Services.jsm");
-
-// This message is used to measure content process startup performance in Talos
-// tests.
-sendAsyncMessage("Content:BrowserChildReady", {
-  time: Services.telemetry.msSystemNow(),
-});

toolkit/content/jar.mn

@@ -39,7 +39,6 @@ toolkit.jar:
    content/global/plugins.html
    content/global/plugins.css
    content/global/plugins.js
-   content/global/browser-child.js
 *   content/global/buildconfig.html
    content/global/buildconfig.css
    content/global/contentAreaUtils.js

toolkit/content/widgets/browser-custom-element.js

@@ -1029,11 +1029,6 @@
         // we should re-evaluate the CSP here.
         this._csp = null;
 
-        this.messageManager.loadFrameScript(
-          "chrome://global/content/browser-child.js",
-          true
-        );
-
         if (!this.hasAttribute("disablehistory")) {
           Services.obs.addObserver(
             this.observer,