[Timeline] Update scroll position on timeout

Fixes #817

platform/features/timeline/src/controllers/TimelineZoomController.js

@@ -28,11 +28,12 @@ define(
          * Controls the pan-zoom state of a timeline view.
          * @constructor
          */
-        function TimelineZoomController($scope, ZOOM_CONFIGURATION) {
+        function TimelineZoomController($scope, $timeout, ZOOM_CONFIGURATION) {
             // Prefer to start with the middle index
             var zoomLevels = ZOOM_CONFIGURATION.levels || [1000],
                 zoomIndex = Math.floor(zoomLevels.length / 2),
                 tickWidth = ZOOM_CONFIGURATION.width || 200,
+                width = tickWidth,
                 bounds = { x: 0, width: tickWidth }; // Default duration in view
 
             function toMillis(pixels) {
@@ -62,6 +63,12 @@ define(
                     zoomIndex += 1;
                 }
                 bounds.x = toPixels(timespan.getStart());
+
+                // Physical width may be insufficient for scroll;
+                // if so, try again on a timeout!
+                if (bounds.x + bounds.width > width) {
+                    $timeout(initializeZoomFromTimespan.bind(null, timespan));
+                }
             }
 
             function initializeZoom() {
@@ -122,7 +129,8 @@ define(
                  */
                 width: function (timestamp) {
                     var pixels = Math.ceil(toPixels(timestamp * (1 + PADDING)));
-                    return Math.max(bounds.width * 2, pixels);
+                    width = Math.max(bounds.width, pixels);
+                    return width;
                 }
             };
         }