Selects do not match width of grid tiles

[andrewseguin]

Since #7083, selects in form fields do not properly adjust their widths when used within grid tiles. When the grid tiles shrink, the select should shrink with it. Instead, they hit their 180px min-width and the content is cut off.

[fxck]

related #7627 (comment)

@mmalerba suggests setting a fixed width on mat-form-field itself, which won't work on any kind of fluid layout..