When using the zero color mask workaround in StateManager9, the blend state and
blend equation were being modified. This caused inconsistant state if the
workaround stopped being used in subsequent draw calls. To deal with this
issue, dirty the BLEND_ENABLED and BLEND_EQUATION states when the COLOR_MASK
changes and dirty the COLOR_MASK state wheneither BLEND_ENABLED or
BLEND_EQUATION changes.
BUG=597107
Change-Id: I689d9cf3c1eb20206a2abc7beff481fc7842f85e
Reviewed-on: https://chromium-review.googlesource.com/340763Reviewed-by: Geoff Lang <geofflang@chromium.org>
