remove prototype pathops code

The original instantiation of pathops was in the experimental/Intersection directory. Anything of value has been copied into the mainline.

The obsolete gyp files are also included, along with a pixman test that never functioned but accidentally referenced some of these deleted files.

Committed: https://skia.googlesource.com/skia/+/17a2b5473d0144d10749ef8d26a10fbdab580226

[caryclark, 2015-01-29 18:29:49]

caryclark@google.com changed reviewers:
+ reed@google.com

[caryclark, 2015-01-29 18:30:25]

The CQ bit was checked by caryclark@google.com

[commit-bot: I haz the power, 2015-01-29 18:31:32]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/867213004/1

[commit-bot: I haz the power, 2015-01-29 18:31:33]

Note for Reviewers:
The CQ is waiting for an approval.
If you believe that the CL is not ready yet, or if you would like to L-G-T-M
with comments then please uncheck the CQ checkbox.

Waiting for LGTM from valid reviewer(s) till 2015-01-30 00:31 UTC

[reed1, 2015-01-29 18:41:06]

lgtm

[commit-bot: I haz the power, 2015-01-29 18:43:13]

Committed patchset #1 (id:1) as
https://skia.googlesource.com/skia/+/17a2b5473d0144d10749ef8d26a10fbdab580226