Correcting color for Toolbar; reverting partially of ag/1585189.

Toolbar also used colorPrimary to get its color, and changing its value
caused the toolbar to have a different color. Going to leave that
unchanged, and introduce a new item_doc_title color for others to use.

Change-Id: I84275a8cc365c7a32fc6ec92f881e289f8d1ed3b