SkThreadPool and co. are not public.

BUG=skia:
R=reed@google.com, mtklein@google.com

Author: mtklein@chromium.org

Review URL: https://codereview.chromium.org/444583006
diff --git a/gyp/utils.gypi b/gyp/utils.gypi
index c90d193..b033573 100644
--- a/gyp/utils.gypi
+++ b/gyp/utils.gypi
@@ -8,9 +8,9 @@
 {
     'sources': [
         # Classes for a threadpool.
-        '<(skia_include_path)/utils/SkCondVar.h',
-        '<(skia_include_path)/utils/SkRunnable.h',
-        '<(skia_include_path)/utils/SkThreadPool.h',
+        '<(skia_src_path)/utils/SkCondVar.h',
+        '<(skia_src_path)/utils/SkRunnable.h',
+        '<(skia_src_path)/utils/SkThreadPool.h',
         '<(skia_src_path)/utils/SkCondVar.cpp',
 
         '<(skia_include_path)/utils/SkBoundaryPatch.h',