Use lowercase windows.h in includes to fix Windows cross compilation using mingw.

Use lowercase windows.h in includes to fix Windows cross compilation using mingw.

While it doesn't matter on Windows, mingw on case-sensitive OSes uses all lower case filenames for platform include files. I found the problem in SkCondVar.h from Mozilla checkout of skia sources, but the patch contains a fix for the whole skia tree.

R=bungeman@google.com

Committed: https://code.google.com/p/skia/source/detail?r=12461

[bungeman-skia, 2013-12-02 15:18:40]

lgtm

Follow up that we may not care to do:
We really shouldn't be including windows.h directly, but instead include
SkTypes.h, which will include required platform headers (like windows.h on
Windows).

[bungeman-skia, 2013-12-03 15:23:45]

Committed patchset #1 manually as r12461.

[cjacek, 2013-12-03 15:25:27]

Thank you.