Fix the rendering error of SkDraw::drawVertices in gpu path for solid color.

If both textures and vertex-colors are NULL, drawVertices should stroke hairlines with the paint's color.
This behavior is a useful debugging mode to visualize the mesh.

BUG=skia:2266
R=bsalomon@google.com, reed@google.com

Author: yunchao.he@intel.com

Review URL: https://codereview.chromium.org/189963004

git-svn-id: http://skia.googlecode.com/svn/trunk/gyp@14985 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/core.gypi b/core.gypi
index 8ffbd1c..2fa559f 100644
--- a/core.gypi
+++ b/core.gypi
@@ -202,6 +202,7 @@
         '<(skia_src_path)/core/SkUnPreMultiply.cpp',
         '<(skia_src_path)/core/SkUtils.cpp',
         '<(skia_src_path)/core/SkValidatingReadBuffer.cpp',
+        '<(skia_src_path)/core/SkVertState.cpp',
         '<(skia_src_path)/core/SkWriteBuffer.cpp',
         '<(skia_src_path)/core/SkWriter32.cpp',
         '<(skia_src_path)/core/SkXfermode.cpp',
@@ -309,6 +310,7 @@
         '<(skia_include_path)/core/SkTypes.h',
         '<(skia_include_path)/core/SkUnPreMultiply.h',
         '<(skia_include_path)/core/SkUtils.h',
+        '<(skia_include_path)/core/SkVertState.h',
         '<(skia_include_path)/core/SkWeakRefCnt.h',
         '<(skia_include_path)/core/SkWriter32.h',
         '<(skia_include_path)/core/SkXfermode.h',