Tab font colors are broken in latest HEAD

[houmark]

Actual Behavior:

• What is the issue? * Tab font colors are broken in current HEAD both for active tabs and non-active.
• What is the expected behavior? Correct tab colors as it was very recently.

CodePen (or steps to reproduce the issue): *

• CodePen Demo which shows your issue: https://material.angularjs.org/HEAD/demo/tabs
• Details: See demo.

Angular Versions: *

• Angular Version: 1.5.8
• Angular Material Version: HEAD

Additional Information:

• Browser Type: * Chrome
• Browser Version: * Latest
• OS: * macOS
• Stack Traces: None.