Fix mixup where SamplePathOverstroke wasn't added

gyp/samples.gypi

 # Copyright 2015 Google Inc.
 #
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 # Include this gypi to include all 'sample' files
 {
   'include_dirs': [
     '../include/views',
     '../experimental',
     '../samplecode',
@@ skipping 60 matching lines @@
     '../samplecode/SampleLitAtlas.cpp',
     '../samplecode/SampleLua.cpp',
     '../samplecode/SampleManyRects.cpp',
     '../samplecode/SampleMeasure.cpp',
     '../samplecode/SampleMegaStroke.cpp',
     '../samplecode/SamplePatch.cpp',
     '../samplecode/SamplePath.cpp',
     '../samplecode/SamplePathClip.cpp',
     '../samplecode/SamplePathFuzz.cpp',
     '../samplecode/SamplePathEffects.cpp',
+    '../samplecode/SamplePathOverstroke.cpp',
     '../samplecode/SamplePictFile.cpp',
     '../samplecode/SamplePoints.cpp',
     '../samplecode/SamplePolyToPoly.cpp',
     '../samplecode/SampleQuadStroker.cpp',
     '../samplecode/SampleRectanizer.cpp',
     '../samplecode/SampleRegion.cpp',
     '../samplecode/SampleRepeatTile.cpp',
     '../samplecode/SampleShaders.cpp',
     '../samplecode/SampleShaderText.cpp',
     '../samplecode/SampleShip.cpp',
@@ skipping 40 matching lines @@
     '../samplecode/SampleFontCache.cpp', #relies on pthread.h
   ],      
   'dependencies': [
     'experimental.gyp:experimental',
     'lua.gyp:lua',
     'pdf.gyp:pdf',
     'views.gyp:views',
     'xml.gyp:xml',
   ],
 }