Bug 1537768 - Simplify RemoteAgent initialization. r=remote-protocol-reviewers,ato

Start the `TabObserver` from `RemoteAgent.listen` in order to prevent
having the tests to manually start it.
Start it from `listen` instead of `init` as we do stop the `TabObserver` from
`stop` and `stop` is the reverse of `listen`, not the reverse of `init`.

Differential Revision: https://phabricator.services.mozilla.com/D29412

--HG--
extra : moz-landing-system : lando

remote/RemoteAgent.jsm

@@ -39,6 +39,10 @@ class RemoteAgentClass {
       throw new Error("Remote agent can only be instantiated from the parent process");
     }
 
+    if (this.server) {
+      return;
+    }
+
     this.server = new HttpServer();
     this.targets = new Targets();
 
@@ -67,7 +71,7 @@ class RemoteAgentClass {
     return !!this.server && !this.server._socketClosed;
   }
 
-  listen(address) {
+  async listen(address) {
     if (!(address instanceof Ci.nsIURI)) {
       throw new TypeError(`Expected nsIURI: ${address}`);
     }
@@ -86,6 +90,10 @@ class RemoteAgentClass {
       return;
     }
 
+    this.init();
+
+    await this.tabs.start();
+
     try {
       this.server._start(port, host);
 
@@ -185,7 +193,6 @@ class RemoteAgentClass {
     this.init();
 
     await Observer.once("sessionstore-windows-restored");
-    await this.tabs.start();
 
     try {
       this.listen(addr);

remote/test/browser/browser_cdp.js

@@ -32,9 +32,7 @@ async function testCDP() {
   const tab = await BrowserTestUtils.openNewForegroundTab(gBrowser, TEST_URI);
 
   // Start the CDP server
-  RemoteAgent.init();
-  RemoteAgent.tabs.start();
-  RemoteAgent.listen(Services.io.newURI("http://localhost:9222"));
+  await RemoteAgent.listen(Services.io.newURI("http://localhost:9222"));
 
   // Retrieve the chrome-remote-interface library object
   const CDP = await getCDP();

remote/test/browser/browser_main_target.js

@@ -11,9 +11,7 @@ const TEST_URI = "data:text/html;charset=utf-8,default-test-page";
 
 add_task(async function() {
   // Start the CDP server
-  RemoteAgent.init();
-  RemoteAgent.tabs.start();
-  RemoteAgent.listen(Services.io.newURI("http://localhost:9222"));
+  await RemoteAgent.listen(Services.io.newURI("http://localhost:9222"));
 
   const { mainProcessTarget } = RemoteAgent.targets;
   ok(mainProcessTarget,

remote/test/browser/browser_page_frameNavigated.js

@@ -31,9 +31,7 @@ async function testCDP() {
   await BrowserTestUtils.openNewForegroundTab(gBrowser, TEST_URI);
 
   // Start the CDP server
-  RemoteAgent.init();
-  RemoteAgent.tabs.start();
-  RemoteAgent.listen(Services.io.newURI("http://localhost:9222"));
+  await RemoteAgent.listen(Services.io.newURI("http://localhost:9222"));
 
   // Retrieve the chrome-remote-interface library object
   const CDP = await getCDP();

remote/test/browser/browser_runtime_evaluate.js

@@ -31,9 +31,7 @@ async function testCDP() {
   await BrowserTestUtils.openNewForegroundTab(gBrowser, TEST_URI);
 
   // Start the CDP server
-  RemoteAgent.init();
-  RemoteAgent.tabs.start();
-  RemoteAgent.listen(Services.io.newURI("http://localhost:9222"));
+  await RemoteAgent.listen(Services.io.newURI("http://localhost:9222"));
 
   // Retrieve the chrome-remote-interface library object
   const CDP = await getCDP();

remote/test/browser/browser_runtime_executionContext.js

@@ -31,9 +31,7 @@ async function testCDP() {
   await BrowserTestUtils.openNewForegroundTab(gBrowser, TEST_URI);
 
   // Start the CDP server
-  RemoteAgent.init();
-  RemoteAgent.tabs.start();
-  RemoteAgent.listen(Services.io.newURI("http://localhost:9222"));
+  await RemoteAgent.listen(Services.io.newURI("http://localhost:9222"));
 
   // Retrieve the chrome-remote-interface library object
   const CDP = await getCDP();

remote/test/browser/browser_tabs.js

@@ -11,9 +11,7 @@ const TEST_URI = "data:text/html;charset=utf-8,default-test-page";
 
 add_task(async function() {
   // Start the CDP server
-  RemoteAgent.init();
-  RemoteAgent.tabs.start();
-  RemoteAgent.listen(Services.io.newURI("http://localhost:9222"));
+  await RemoteAgent.listen(Services.io.newURI("http://localhost:9222"));
 
   const CDP = await getCDP();
 

remote/test/browser/browser_target.js

@@ -26,9 +26,7 @@ add_task(async function() {
 
 async function testCDP() {
   // Start the CDP server
-  RemoteAgent.init();
-  RemoteAgent.tabs.start();
-  RemoteAgent.listen(Services.io.newURI("http://localhost:9222"));
+  await RemoteAgent.listen(Services.io.newURI("http://localhost:9222"));
 
   // Retrieve the chrome-remote-interface library object
   const CDP = await getCDP();