Scrum work board with time tracking poorly handles issues with time tracking hidden in field config

Steps to repro:

1. Create a new project, simple everything, and a scrum board. Enable time tracking on the board.
2. Create a new field configuration
3. Hide the Time Tracking field in the new field config
4. Make a new field config scheme and apply the field configuration to subtasks only
5. Create an issue, and a subtask for it
6. Try and view it in the issue details pane of the work board.

If you deminify, then you get something like:

Exception: Uncaught TypeError: Cannot read property 'text' of undefined
Resource: http://127.0.0.1:8080/s/en_US5xjk68-418945332/852/5/35af1158b4a88288c986eb482225490c/_/download/contextbatch/js/gh-rapid/batch.js
Line: 45624

Which points to:

GH.tpl.detailview.renderTextView = function(opt_data, opt_sb) {
  var output = opt_sb || new soy.StringBuilder();
  output.append((opt_data.field.text) ? soy.$$escapeHtml(opt_data.field.text) : '<span class="ghx-fa">' + ((opt_data.field.type == 'number') ? '&nbsp;' : soy.$$escapeHtml("None")) + '</span>');
  return opt_sb ? '' : output.toString();
};

Workaround:

Unhide the Time Tracking field in your field configuration.

We should either throw a usable error message that an end user or admin can action on, or handle it somehow.