Don't apply color filter on header icons if animations are disabled.

Disabling animations altogether reduces the flakiness, however, icon's alpha seem to be changed and then cleared, and there was 1 out of 24 runs where it flaked; so, avoiding the toggle of alpha when animations are disabled.

Bug: 337916664
Test: Screenshot tests
Flag: N/A
Change-Id: I4e9d703d005e3916ee01cf74baa2a804a3c1efd1