Make GrClip.h private

BUG=skia:

Change-Id: I4aa3c2707811ece3a63d161035e316c3bbc1cd15
Reviewed-on: https://skia-review.googlesource.com/9482
Commit-Queue: Brian Salomon <bsalomon@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
diff --git a/tests/RectangleTextureTest.cpp b/tests/RectangleTextureTest.cpp
index ef5f2d3..0f164eb 100644
--- a/tests/RectangleTextureTest.cpp
+++ b/tests/RectangleTextureTest.cpp
@@ -9,12 +9,13 @@
 #include "TestUtils.h"
 
 #if SK_SUPPORT_GPU
+#include "GrClip.h"
 #include "GrContext.h"
 #include "GrContextPriv.h"
 #include "GrRenderTargetContext.h"
+#include "gl/GLTestContext.h"
 #include "gl/GrGLGpu.h"
 #include "gl/GrGLUtil.h"
-#include "gl/GLTestContext.h"
 
 // skbug.com/5932
 static void test_basic_draw_as_src(skiatest::Reporter* reporter, GrContext* context,