code: function(modeSpec, highlightImmediately) {
  			if (!modeSpec) { return; }
  			this.mode = this.codeMirror.getMode(this.codeMirror.options, modeSpec);
  			this.lines = this._newLines(this.model.getLineCount());
  			if (highlightImmediately) {
  				this.highlight();
  			}
  		}
docs: Sets the CodeMirror mode to be used for highlighting. The mode must be registered with the {@link orion.mirror.Mirror}
  that this <code>ModeApplier</code> was created with. (The methods {@link orion.mirror.Mirror#defineMode} and
  {@link orion.mirror.Mirror#defineMIME} can be used to register a mode with a Mirror.)
  @param {String} modeSpec Mode name or MIME type.
  @param {Boolean} [highlightImmediately=false]