optimize pathops coverage

optimize pathops coverage

Remove unused code from SkOpSegment.cpp and friends. 
Add new tests exposed by coverage.
Fix a bug exposed by coverage -- removing the need to detect points that are nearby when intersecting.
Add gyp rule for building coverage flavor on Mac.

Committed: http://code.google.com/p/skia/source/detail?r=12344

[caryclark, 2013-11-21 14:27:12]

MIke, you're welcome to review all of this CL, but I'm mostly interested in a
sanity check on the gyp change.

Thanks

[mtklein, 2013-11-21 16:33:24]

lgtm

https://codereview.chromium.org/75453003/diff/90001/gyp/common_conditions.gypi
File gyp/common_conditions.gypi (right):

https://codereview.chromium.org/75453003/diff/90001/gyp/common_conditions.gyp...
gyp/common_conditions.gypi:344: 'GCC_INSTRUMENT_PROGRAM_FLOW_ARCS' : 'YES',
Extra space here before :

https://codereview.chromium.org/75453003/diff/90001/gyp/common_conditions.gyp...
gyp/common_conditions.gypi:346: },
When I patch this on 10.9, I get an out/Coverage to build, but no coverage flags
are passed to the compiler and linker.  Neither gcda nor gcno are generated.

I've tried the direct approach,
  'OTHER_CFLAGS':         ['--coverage'],
  'OTHER_CPLUSPLUSFLAGS': ['--coverage'],
  'target_conditions': [
    ['_type == "executable"', {
      'OTHER_LDFLAGS': [ '--coverage' ],
    }],
  ],
but I'm struggling to get the linker --coverage flag to do the right thing,
though it's working great for me on a little 2-file toy example.  Not sure
what's wrong.  If this works for you let's submit it and I can fiddle around
later.

[commit-bot: I haz the power, 2013-11-21 16:53:07]

CQ is trying da patch. Follow status at
https://skia-tree-status.appspot.com/cq/caryclark@google.com/75453003/90001

[commit-bot: I haz the power, 2013-11-21 17:04:36]

Change committed as 12344