impressConsole broke init() if root element didn't have id="impress"

Also adds regression tests to prevent this from happening in the future
as well as upgrades karma-chrome-launcher to newest version.

Fixes #654

js/impress.js

@@ -2487,21 +2487,13 @@
         var init = function( cssConsole, cssIframe ) {
             if ( ( cssConsole === undefined || cssConsole === cssFileOldDefault ) &&
                  ( cssIframe === undefined  || cssIframe === cssFileIframeOldDefault ) ) {
-                window.console.log( 'impressConsole.init() is deprecated. ' +
+                window.console.log( 'impressConsole().init() is deprecated. ' +
                                    'impressConsole is now initialized automatically when you ' +
                                    'call impress().init().' );
             }
             _init( cssConsole, cssIframe );
         };
 
-        document.addEventListener( 'impress:init', function() {
-            _init();
-
-            // Add 'P' to the help popup
-            triggerEvent( document, 'impress:help:add',
-                         { command: 'P', text: 'Presenter console', row: 10 } );
-        } );
-
         // New API for impress.js plugins is based on using events
         root.addEventListener( 'impress:console:open', function() {
             window.open();
@@ -2520,11 +2512,21 @@
 
         // Return the object
         allConsoles[ rootId ] = { init: init, open: open, clockTick: clockTick,
-                               registerKeyEvent: registerKeyEvent };
+                               registerKeyEvent: registerKeyEvent, _init: _init };
         return allConsoles[ rootId ];
 
     };
 
+    // This initializes impressConsole automatically when initializing impress itself
+    document.addEventListener( 'impress:init', function(event) {
+        // impressConsole wants the id string, not the DOM element directly
+        impressConsole(event.target.id)._init();
+
+        // Add 'P' to the help popup
+        triggerEvent( document, 'impress:help:add',
+                        { command: 'P', text: 'Presenter console', row: 10 } );
+    } );
+
     // Returns a string to be used inline as a css <style> element in the console window.
     // Apologies for length, but hiding it here at the end to keep it away from rest of the code.
     var cssStyleStr = function() {
@@ -2671,8 +2673,6 @@
         </style>`;
     };
 
-    impressConsole();
-
 } )( document, window );
 
 /**