Switching the patch range in gr-file-list triggers a number of REST
calls which may take multiple seconds to resolve -- especially on large
changes. During the time that these requests are in flight, the file
rows and delta information no longer accurately reflects the selected
patch range, and no visual indicator is presented regarding whether the
requests have resolved.
With this change, file list information is grayed out while the reload
requests are in flight.
Bug: Issue 6925
Change-Id: I69f95afc5af00a8c6348e05e3d88ed07b4c019c1
89ac00fe01