Addressing Anton's comments on PR 869.

Removed extra check for console.log() existance. Modified error
messages. Formatted entire file to fit in 80 lines or less.

Formatting files so that they fit under 80 lines. Adding debug info for
what type of YouTube video player is being used. Also comment on whether
playbackRates is available for HTML5 mode.

Changed back Anton's original function _checkPlaybackRates(). Now logging for
this function's result is done only on error (in the function that is invoking)
it).

common/lib/xmodule/xmodule/js/src/video/08_video_speed_control.js

@@ -19,6 +19,10 @@ function () {
         }
 
         if (state.videoType === 'html5' && !(_checkPlaybackRates())) {
+            console.log(
+                '[Video info]: HTML5 mode - playbackRate is not supported.'
+            );
+
             _hideSpeedControl(state);
 
             return;
@@ -65,7 +69,7 @@ function () {
             state.videoSpeedControl.el
         );
 
-        $.each(state.videoSpeedControl.speeds, function(index, speed) {
+        $.each(state.videoSpeedControl.speeds, function (index, speed) {
             var link = '<a class="speed_link" href="#">' + speed + 'x</a>';
 
             state.videoSpeedControl.videoSpeedsEl
@@ -78,26 +82,27 @@ function () {
     }
 
     /**
-    * @desc Check if playbackRate supports by browser.
-    *
-    * @type {function}
-    * @access private
-    *
-    * @param {object} state The object containg the state of the video player.
-    *     All other modules, their parameters, public variables, etc. are
-    *     available via this object.
-    *
-    * @this {object} The global window object.
-    *
-    * @returns {Boolean}
-    *       true: Browser support playbackRate functionality.
-    *       false: Browser doesn't support playbackRate functionality.
-    */
+     * @desc Check if playbackRate supports by browser.
+     *
+     * @type {function}
+     * @access private
+     *
+     * @param {object} state The object containg the state of the video player.
+     *     All other modules, their parameters, public variables, etc. are
+     *     available via this object.
+     *
+     * @this {object} The global window object.
+     *
+     * @returns {Boolean}
+     *       true: Browser support playbackRate functionality.
+     *       false: Browser doesn't support playbackRate functionality.
+     */
     function _checkPlaybackRates() {
         var video = document.createElement('video');
 
-        // If browser supports, 1.0 should be returned by playbackRate property.
-        // In this case, function return True. Otherwise, False will be returned.
+        // If browser supports, 1.0 should be returned by playbackRate
+        // property. In this case, function return True. Otherwise, False will
+        // be returned.
         return Boolean(video.playbackRate);
     }
 
@@ -128,7 +133,7 @@ function () {
             .on('click', state.videoSpeedControl.changeVideoSpeed);
 
         if (onTouchBasedDevice()) {
-            state.videoSpeedControl.el.on('click', function(event) {
+            state.videoSpeedControl.el.on('click', function (event) {
                 // So that you can't highlight this control via a drag
                 // operation, we disable the default browser actions on a
                 // click event.
@@ -287,7 +292,7 @@ function () {
         this.videoSpeedControl.videoSpeedsEl.find('li').removeClass('active');
         this.videoSpeedControl.speeds = params.newSpeeds;
 
-        $.each(this.videoSpeedControl.speeds, function(index, speed) {
+        $.each(this.videoSpeedControl.speeds, function (index, speed) {
             var link, listItem;
 
             link = '<a class="speed_link" href="#">' + speed + 'x</a>';