Make collapsing toolbar load font synchronously

Since collapsing toolbar might load the font asynchronously, it caused
that some settings pages are seeing a flicker on its title. This change
is using TextAppearanceConfig.setShouldLoadFontSynchronously(true)
method to have title font load synchronously, which would remove the
flicker problem.

Fixes: 182232144
Test: visual verified
1) Enable developer options
2) Settings > System > Developer options
3) See if there's a flicker on title

Change-Id: I4e1db1a0fae9f69c7ff5baca7ada49c08f1bcbea