Also tint the settings icon in DashboardAdapter.setCategory().

When suggestion loader takes longer time to complete, we will first show
the dashboard with just the categories, and refresh the UI when the
suggestion is ready. However, we only tint the icon when we update both
the categories and suggestions, and hence in some case, some tile
results with icon not being tinted.

Change-Id: I023d50655349731b03c7d7aff153d2cbbd8c63e0
Fix: 37456962
Test: make RunSettingsRoboTests