Fine tune list item layout and remove summary column

Use weight to get dynamic width preview icon will show or hide.
If preview icon hide, there will have a large space on second line.

Remove summary column due to it is not showing currently on both
phone and tablet, summary column is just only using for show
progress of downloading files.

Fix: 122344258
Test: visual
Test: atest DocumentsUITests
Change-Id: I79f888fdbd659e37bc601f0c637eddca27dc94b9