Make the unix test app build.

There are two ways to build it, using the gyp files,
or using its own makefile.  A recent update of a
sample made it no longer build using its own makefile.
Make it build once again.


git-svn-id: http://skia.googlecode.com/svn/trunk@1236 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/unix_test_app/makefile b/unix_test_app/makefile
index ae2f338..7b28203 100644
--- a/unix_test_app/makefile
+++ b/unix_test_app/makefile
@@ -10,7 +10,8 @@
               -I../include/gpu \
               -I../gpu/include \
               -I../include/utils/unix \
-              -I../samplecode
+              -I../samplecode \
+              -I../src/core
 
 VPATH = libs:../src/ports:../samplecode:../src/core:../src/utils/unix