Revert of Revert of Rename kPMColor_SkColorType to kN32_SkColorType.

Revert of Revert of Rename kPMColor_SkColorType to kN32_SkColorType. (https://codereview.chromium.org/234243002/)

Reason for revert:
Want to reland the original CL.

Original issue's description:
> Revert of Rename kPMColor_SkColorType to kN32_SkColorType. (https://codereview.chromium.org/227433009/)
> 
> Reason for revert:
> breaking the Chrome deps roll.
> http://build.chromium.org/p/chromium.linux/builders/Linux%20GN%20%28dbg%29/builds/839/steps/compile/logs/stdio
> 
> Original issue's description:
> > Rename kPMColor_SkColorType to kN32_SkColorType.
> > 
> > The new name better represents what this flag means.
> > 
> > BUG=skia:2384
> > 
> > Committed: http://code.google.com/p/skia/source/detail?r=14117
> 
> TBR=reed@google.com,scroggo@google.com
> NOTREECHECKS=true
> NOTRY=true
> BUG=skia:2384
> 
> Committed: http://code.google.com/p/skia/source/detail?r=14144

TBR=reed@google.com,bensong@google.com
NOTREECHECKS=true
NOTRY=true
BUG=skia:2384
Committed: http://code.google.com/p/skia/source/detail?r=14156

[scroggo, 2014-04-11 17:14:53]

Created Revert of Revert of Rename kPMColor_SkColorType to kN32_SkColorType.

[commit-bot: I haz the power, 2014-04-11 17:14:57]

CQ is trying da patch. Follow status at
https://skia-tree-status.appspot.com/cq/scroggo@google.com/235523003/1

[commit-bot: I haz the power, 2014-04-11 17:16:13]

Change committed as 14156