Bug 1454373 - Switch protocol.js to native promises. r=jryans

MozReview-Commit-ID: ALifNayHJJG

--HG--
extra : rebase_source : 4f1a2ee628785850e1b4ca406d5f4c10d3ce6262

devtools/server/tests/unit/test_protocol_stack.js

@@ -76,7 +76,7 @@ function run_test() {
       let stack = Components.stack;
       while (stack) {
         info(stack.name);
-        if (stack.name == "onConnect") {
+        if (stack.name.includes("run_test/onConnect")) {
           // Reached back to outer function before request
           ok(true, "Complete stack");
           return;

devtools/shared/defer.js

@@ -4,7 +4,9 @@
 
 "use strict";
 
-// See bug 1273941 to understand this choice of promise.
+// We have to keep using Promise.jsm here, because DOM Promises
+// start freezing during panel iframes destruction.
+// More info in bug 1454373 comment 15.
 const Promise = require("promise");
 
 /**

devtools/shared/protocol.js

@@ -4,14 +4,27 @@
 
 "use strict";
 
-var promise = require("promise");
-var defer = require("devtools/shared/defer");
 const { extend } = require("devtools/shared/extend");
 var EventEmitter = require("devtools/shared/event-emitter");
 var {getStack, callFunctionWithAsyncStack} = require("devtools/shared/platform/stack");
 var {settleAll} = require("devtools/shared/DevToolsUtils");
 var {lazyLoadSpec, lazyLoadFront} = require("devtools/shared/specs/index");
 
+// Bug 1454373: devtools/shared/defer still uses Promise.jsm which is slower
+// than DOM Promises. So implement our own copy of `defer` based on DOM Promises.
+function defer() {
+  let resolve, reject;
+  let promise = new Promise(function() {
+    resolve = arguments[0];
+    reject = arguments[1];
+  });
+  return {
+    resolve: resolve,
+    reject: reject,
+    promise: promise
+  };
+}
+
 /**
  * Types: named marshallers/demarshallers.
  *
@@ -983,7 +996,7 @@ Actor.prototype = extend(Pool.prototype, {
   },
 
   _queueResponse: function(create) {
-    let pending = this._pendingResponse || promise.resolve(null);
+    let pending = this._pendingResponse || Promise.resolve(null);
     let response = create(pending);
     this._pendingResponse = response;
   }
@@ -1248,7 +1261,7 @@ Front.prototype = extend(Pool.prototype, {
    * represents.
    */
   actor: function() {
-    return promise.resolve(this.actorID);
+    return Promise.resolve(this.actorID);
   },
 
   toString: function() {
@@ -1314,7 +1327,7 @@ Front.prototype = extend(Pool.prototype, {
         // Check to see if any of the preEvents returned a promise -- if so,
         // wait for their resolution before emitting. Otherwise, emit synchronously.
         if (results.some(result => result && typeof result.then === "function")) {
-          promise.all(results).then(() => {
+          Promise.all(results).then(() => {
             return EventEmitter.emit.apply(null, [this, event.name].concat(args));
           });
           return;