Bug 1446222 - Move DevTools frame startup to new dir. r=jdescottes

Move and rename the server's frame script that starts DevTools in remote frames
from `child.js` to `startup/frame.js`.  `connectToChild` also becomes the more
generic `connectToFrame`.  A few b2g-isms like "app" are also removed.

These code paths will likely change more as Site Isolation work continues, but
for now, we have this light cleanup to gather startup-related paths together.

MozReview-Commit-ID: El8a0OE99gZ

--HG--
rename : devtools/server/child.js => devtools/server/startup/frame.js
rename : devtools/server/tests/mochitest/test_connectToChild.html => devtools/server/tests/mochitest/test_connectToFrame.html
extra : rebase_source : 2735c53587257b215d720204cf7c4581088eba42

devtools/client/framework/target.js

@@ -407,7 +407,7 @@ TabTarget.prototype = {
       DebuggerServer.init();
 
       // When connecting to a local tab, we only need the root actor.
-      // Then we are going to call DebuggerServer.connectToChild and talk
+      // Then we are going to call DebuggerServer.connectToFrame and talk
       // directly with actors living in the child process.
       // We also need browser actors for actor registry which enabled addons
       // to register custom actors.

devtools/client/responsive.html/browser/tunnel.js

@@ -448,7 +448,7 @@ MessageManagerTunnel.prototype = {
 
   OUTER_TO_INNER_FRAME_SCRIPTS: [
     // DevTools server for OOP frames
-    "resource://devtools/server/child.js"
+    "resource://devtools/server/startup/frame.js"
   ],
 
   get outer() {

devtools/server/actors/webbrowser.js

@@ -721,7 +721,7 @@ BrowserTabActor.prototype = {
       }
       this.exit();
     };
-    let connect = DebuggerServer.connectToChild(this._conn, this._browser, onDestroy);
+    let connect = DebuggerServer.connectToFrame(this._conn, this._browser, onDestroy);
     let form = await connect;
 
     this._form = form;

devtools/server/actors/webextension-parent.js

@@ -161,7 +161,7 @@ ProxyChildActor.prototype = {
 
     this._browser = await ExtensionParent.DebugUtils.getExtensionProcessBrowser(this);
 
-    this._form = await DebuggerServer.connectToChild(this._conn, this._browser, onDestroy,
+    this._form = await DebuggerServer.connectToFrame(this._conn, this._browser, onDestroy,
                                                      {addonId: this.addonId});
 
     this._childActorID = this._form.actor;

devtools/server/actors/webextension.js

@@ -47,7 +47,7 @@ const FALLBACK_DOC_MESSAGE = "Your addon does not have any document opened yet."
  *        The connection to the client.
  * @param {nsIMessageSender} chromeGlobal.
  *        The chromeGlobal where this actor has been injected by the
- *        DebuggerServer.connectToChild method.
+ *        DebuggerServer.connectToFrame method.
  * @param {string} prefix
  *        the custom RDP prefix to use.
  * @param {string} addonId

devtools/server/main.js

@@ -973,12 +973,13 @@ var DebuggerServer = {
   _childMessageManagers: new Set(),
 
   /**
-   * Connect to a child process.
+   * Start a DevTools server in a remote frame's process and add it as a child server for
+   * an active connection.
    *
    * @param object connection
    *        The debugger server connection to use.
    * @param nsIDOMElement frame
-   *        The browser element that holds the child process.
+   *        The frame element with remote content to connect to.
    * @param function [onDestroy]
    *        Optional function to invoke when the child process closes
    *        or the connection shuts down. (Need to forget about the
@@ -987,12 +988,12 @@ var DebuggerServer = {
    *         A promise object that is resolved once the connection is
    *         established.
    */
-  connectToChild(connection, frame, onDestroy, {addonId} = {}) {
+  connectToFrame(connection, frame, onDestroy, {addonId} = {}) {
     return new Promise(resolve => {
       // Get messageManager from XUL browser (which might be a specialized tunnel for RDM)
       // or else fallback to asking the frameLoader itself.
       let mm = frame.messageManager || frame.frameLoader.messageManager;
-      mm.loadFrameScript("resource://devtools/server/child.js", false);
+      mm.loadFrameScript("resource://devtools/server/startup/frame.js", false);
 
       let trackMessageManager = () => {
         frame.addEventListener("DevTools:BrowserSwap", onBrowserSwap);
@@ -1021,7 +1022,7 @@ var DebuggerServer = {
       // between e10s parent and child processes
       let parentModules = [];
       let onSetupInParent = function(msg) {
-        // We may have multiple connectToChild instance running for the same tab
+        // We may have multiple connectToFrame instance running for the same tab
         // and need to filter the messages.
         if (msg.json.prefix != connPrefix) {
           return false;
@@ -1067,7 +1068,7 @@ var DebuggerServer = {
 
         connection.setForwarding(prefix, childTransport);
 
-        dumpn("establishing forwarding for app with prefix " + prefix);
+        dumpn(`Start forwarding for frame with prefix ${prefix}`);
 
         actor = msg.json.actor;
         resolve(actor);
@@ -1129,14 +1130,14 @@ var DebuggerServer = {
             // Nothing to do
           }
         } else {
-          // Otherwise, the app has been closed before the actor
+          // Otherwise, the frame has been closed before the actor
           // had a chance to be created, so we are not able to create
           // the actor.
           resolve(null);
         }
         if (actor) {
           // The ContentActor within the child process doesn't necessary
-          // have time to uninitialize itself when the app is closed/killed.
+          // have time to uninitialize itself when the frame is closed/killed.
           // So ensure telling the client that the related actor is detached.
           connection.send({ from: actor.actor, type: "tabDetached" });
           actor = null;

devtools/server/moz.build

@@ -10,6 +10,7 @@ DIRS += [
     'actors',
     'performance',
     'socket',
+    'startup',
 ]
 
 BROWSER_CHROME_MANIFESTS += ['tests/browser/browser.ini']
@@ -17,7 +18,6 @@ MOCHITEST_CHROME_MANIFESTS += ['tests/mochitest/chrome.ini']
 XPCSHELL_TESTS_MANIFESTS += ['tests/unit/xpcshell.ini']
 
 DevToolsModules(
-    'child.js',
     'content-process-debugger-server.js',
     'content-server.jsm',
     'main.js',

devtools/server/startup/frame.js

@@ -6,6 +6,12 @@
 
 /* global addEventListener, addMessageListener, removeMessageListener, sendAsyncMessage */
 
+/*
+ * Frame script that listens for requests to start a `DebuggerServer` for a frame in a
+ * content process.  Loaded into content process frames by the main process during
+ * `DebuggerServer.connectToFrame`.
+ */
+
 try {
   var chromeGlobal = this;
 
@@ -128,5 +134,5 @@ try {
     });
   })();
 } catch (e) {
-  dump(`Exception in app child process: ${e}\n`);
+  dump(`Exception in DevTools frame startup: ${e}\n`);
 }

devtools/server/startup/moz.build

@@ -0,0 +1,9 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# 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/.
+
+DevToolsModules(
+    'frame.js',
+)

devtools/server/tests/mochitest/chrome.ini

@@ -31,7 +31,7 @@ support-files =
   webextension-helpers.js
 [test_animation_actor-lifetime.html]
 [test_connection-manager.html]
-[test_connectToChild.html]
+[test_connectToFrame.html]
 [test_css-logic.html]
 [test_css-logic-media-queries.html]
 [test_css-logic-specificity.html]

devtools/server/tests/mochitest/test_connectToFrame.html

@@ -1,7 +1,7 @@
 <!DOCTYPE HTML>
 <html>
 <!--
-Bug 966991 - Test DebuggerServer.connectToChild
+Bug 966991 - Test DebuggerServer.connectToFrame
 -->
 <head>
   <meta charset="utf-8">
@@ -78,7 +78,7 @@ function runTests() {
     let transport = DebuggerServer.connectPipe();
     let conn = transport._serverConnection;
     let client = new DebuggerClient(transport);
-    DebuggerServer.connectToChild(conn, iframe).then(actor => {
+    DebuggerServer.connectToFrame(conn, iframe).then(actor => {
       ok(actor.testActor, "Got the test actor");
 
       // Ensure sending at least one request to our actor,
@@ -107,7 +107,7 @@ function runTests() {
     let transport = DebuggerServer.connectPipe();
     let conn = transport._serverConnection;
     let client = new DebuggerClient(transport);
-    DebuggerServer.connectToChild(conn, iframe).then(actor => {
+    DebuggerServer.connectToFrame(conn, iframe).then(actor => {
       ok(actor.testActor, "Got a test actor for the second connection");
       isnot(actor.testActor, firstActor,
             "We get different actor instances between two connections");

devtools/server/tests/mochitest/test_setupInParentChild.html

@@ -80,7 +80,7 @@ function runTests() {
   Services.obs.addObserver(onParent, "test:setupParent");
 
   // Instanciate e10s machinery and call setupInChild
-  DebuggerServer.connectToChild(conn, iframe).then(actor => {
+  DebuggerServer.connectToFrame(conn, iframe).then(actor => {
     DebuggerServer.setupInChild({
       module: "chrome://mochitests/content/chrome/devtools/server/tests/mochitest/setup-in-child.js",
       setupChild: "setupChild",