[CCA] Convert background_ops.js into ES6 module.

Bug: 141518780
Test: Pass closure compiler check, tast run <DUT> 'camera.CCAUI*' on both HALv1
and v3 devices.

Change-Id: I10d4a870ba2495b0338e412dcdf1791129868c56
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1989287Reviewed-by: Shik Chen <shik@chromium.org>
Commit-Queue: Kuo Jen Wei <inker@chromium.org>
Auto-Submit: Kuo Jen Wei <inker@chromium.org>
Cr-Commit-Position: refs/heads/master@{#728832}

chrome/browser/resources/chromeos/camera/src/js/background_ops.js

@@ -2,23 +2,16 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-'use strict';
-
-/**
- * Namespace for the Camera app.
- */
-var cca = cca || {};
-
-/**
- * Namespace for the background page.
- */
-cca.bg = cca.bg || {};
+// eslint-disable-next-line no-unused-vars
+import {Intent} from './intent.js';
+// eslint-disable-next-line no-unused-vars
+import {PerfLogger} from './perf.js';
 
 /**
  * Operations supported by foreground window.
  * @interface
  */
-cca.bg.ForegroundOps = class {
+export class ForegroundOps {
   /**
    * Suspend foreground window.
    * @return {!Promise}
@@ -31,29 +24,29 @@ cca.bg.ForegroundOps = class {
    * @abstract
    */
   resume() {}
-};
+}
 
 /**
  * Operations supported by background window.
  * @interface
  */
-cca.bg.BackgroundOps = class {
+export class BackgroundOps {
   /**
    * Sets the implementation of ForegroundOps from foreground window.
-   * @param {!cca.bg.ForegroundOps} ops
+   * @param {!ForegroundOps} ops
    */
   bindForegroundOps(ops) {}
 
   /**
-   * Gets intent associate with cca.bg.Window object.
-   * @return {?cca.intent.Intent}
+   * Gets intent associate with CCA Window object.
+   * @return {?Intent}
    * @abstract
    */
   getIntent() {}
 
   /**
-   * Gets the perf logger associate with cca.bg.Window object.
-   * @return {!cca.perf.PerfLogger}
+   * Gets the perf logger associate with CCA Window object.
+   * @return {!PerfLogger}
    * @abstract
    */
   getPerfLogger() {}
@@ -69,4 +62,9 @@ cca.bg.BackgroundOps = class {
    * @abstract
    */
   notifySuspension() {}
-};
+}
+
+/** @const */
+cca.bg.ForegroundOps = ForegroundOps;
+/** @const */
+cca.bg.BackgroundOps = BackgroundOps;

chrome/browser/resources/chromeos/camera/src/js/namespace.js

@@ -9,6 +9,7 @@
 
 // eslint-disable-next-line no-unused-vars
 var cca = {
+  bg: {},
   device: {},
   intent: {},
   metrics: {},

chrome/browser/resources/chromeos/camera/src/views/background.html

@@ -12,7 +12,6 @@
     <script type="module" src="../js/type.js"></script>
     <script type="module" src="../js/perf.js"></script>
     <script type="module" src="../js/intent.js"></script>
-    <script defer src="../js/background_ops.js"></script>
     <script defer src="../js/background.js"></script>
   </head>
 </html>