Rename test files to end with Test.cpp.

Rename test files to end with Test.cpp.

DM builds all of {bench,gm,test}/*.cpp.  A Windows build warned us that we were
trying to link typeface.obj twice.  This must have something to do with there
existing gm/typeface.cpp and tests/Typeface.cpp.  To be safe, make sure tests
have a Test.cpp suffix to disambiguate.

BUG=skia:

Committed: http://code.google.com/p/skia/source/detail?r=13644

[rmistry, 2014-03-03 18:24:42]

LGTM

[mtklein, 2014-03-03 18:25:54]

The CQ bit was checked by mtklein@google.com

[commit-bot: I haz the power, 2014-03-03 18:25:59]

CQ is trying da patch. Follow status at
https://skia-tree-status.appspot.com/cq/mtklein@chromium.org/185923002/1

[commit-bot: I haz the power, 2014-03-03 19:23:33]

Change committed as 13644