[CCA] Migrate cca.views.camera.RecordTime to ES6 class

Bug: b/141518780
Test: Pass closure compiler check, tast run <DUT> 'camera.CCAUI*' and
validate all function of CCA on HALv1/v3 device works correctly.

Change-Id: I7fd2182d5e1933ab7dd282850f0010d0d0c9b26b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1954996Reviewed-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@{#724509}

chrome/browser/resources/chromeos/camera/src/js/views/camera/recordtime.js

@@ -20,81 +20,82 @@ cca.views = cca.views || {};
 cca.views.camera = cca.views.camera || {};
 
 /**
- * Creates a controller for the record-time of Camera view.
- * @constructor
+ * Controller for the record-time of Camera view.
  */
-cca.views.camera.RecordTime = function() {
+cca.views.camera.RecordTime = class {
   /**
-   * @type {!HTMLElement}
-   * @private
+   * @public
    */
-  this.recordTime_ =
-      /** @type {!HTMLElement} */ (document.querySelector('#record-time'));
+  constructor() {
+    /**
+     * @type {!HTMLElement}
+     * @private
+     */
+    this.recordTime_ =
+        /** @type {!HTMLElement} */ (document.querySelector('#record-time'));
+
+    /**
+     * Timeout to count every tick of elapsed recording time.
+     * @type {?number}
+     * @private
+     */
+    this.tickTimeout_ = null;
+
+    /**
+     * Tick count of elapsed recording time.
+     * @type {number}
+     * @private
+     */
+    this.ticks_ = 0;
+  }
 
   /**
-   * Timeout to count every tick of elapsed recording time.
-   * @type {?number}
+   * Updates UI by the elapsed recording time.
+   * @param {number} time Time in seconds.
    * @private
    */
-  this.tickTimeout_ = null;
+  update_(time) {
+    // Format time into HH:MM:SS or MM:SS.
+    var pad = (n) => {
+      return (n < 10 ? '0' : '') + n;
+    };
+    var hh = '';
+    if (time >= 3600) {
+      hh = pad(Math.floor(time / 3600)) + ':';
+    }
+    var mm = pad(Math.floor(time / 60) % 60) + ':';
+    document.querySelector('#record-time-msg').textContent =
+        hh + mm + pad(time % 60);
+  }
 
   /**
-   * Tick count of elapsed recording time.
-   * @type {number}
-   * @private
+   * Starts to count and show the elapsed recording time.
    */
-  this.ticks_ = 0;
-
-  // End of properties, seal the object.
-  Object.seal(this);
-};
+  start() {
+    this.update_(0);
+    this.recordTime_.hidden = false;
 
-/**
- * Updates UI by the elapsed recording time.
- * @param {number} time Time in seconds.
- * @private
- */
-cca.views.camera.RecordTime.prototype.update_ = function(time) {
-  // Format time into HH:MM:SS or MM:SS.
-  var pad = (n) => {
-    return (n < 10 ? '0' : '') + n;
-  };
-  var hh = '';
-  if (time >= 3600) {
-    hh = pad(Math.floor(time / 3600)) + ':';
+    this.ticks_ = 0;
+    this.tickTimeout_ = setInterval(() => {
+      this.ticks_++;
+      this.update_(this.ticks_);
+    }, 1000);
   }
-  var mm = pad(Math.floor(time / 60) % 60) + ':';
-  document.querySelector('#record-time-msg').textContent =
-      hh + mm + pad(time % 60);
-};
-
-/**
- * Starts to count and show the elapsed recording time.
- */
-cca.views.camera.RecordTime.prototype.start = function() {
-  this.update_(0);
-  this.recordTime_.hidden = false;
-
-  this.ticks_ = 0;
-  this.tickTimeout_ = setInterval(() => {
-    this.ticks_++;
-    this.update_(this.ticks_);
-  }, 1000);
-};
 
-/**
- * Stops counting and showing the elapsed recording time.
- * @return {number} Recorded time in 1 minute buckets.
- */
-cca.views.camera.RecordTime.prototype.stop = function() {
-  cca.toast.speak('status_msg_recording_stopped');
-  if (this.tickTimeout_) {
-    clearInterval(this.tickTimeout_);
-    this.tickTimeout_ = null;
+  /**
+   * Stops counting and showing the elapsed recording time.
+   * @return {number} Recorded time in 1 minute buckets.
+   */
+  stop() {
+    cca.toast.speak('status_msg_recording_stopped');
+    if (this.tickTimeout_) {
+      clearInterval(this.tickTimeout_);
+      this.tickTimeout_ = null;
+    }
+    var mins = Math.ceil(this.ticks_ / 60);
+    this.ticks_ = 0;
+    this.recordTime_.hidden = true;
+    this.update_(0);
+    return mins;
   }
-  var mins = Math.ceil(this.ticks_ / 60);
-  this.ticks_ = 0;
-  this.recordTime_.hidden = true;
-  this.update_(0);
-  return mins;
 };