Load more than 10 discussions in compacted views.

Currently set to 2x default in "full" compact view (i.e. full topic header is shown),
and 3x default in "one-line" compact view (i.e. only topic title is shown).

Bug: 58407
Change-Id: Ie5b23b93fb6094b4971ee29e93eaa4c1d7f90aa0
Merge "Load more than 10 discussions in compacted views."