Revert[8] "replace SkXfermode obj with SkBlendMode enum in paints"

src/core/SkBlendModePriv.h

Index: src/core/SkBlendModePriv.h
diff --git a/src/core/SkBlendModePriv.h b/src/core/SkBlendModePriv.h
new file mode 100644
index 0000000000000000000000000000000000000000..b5d9e751e62de45f79f423b5a26d214db54d3938
--- /dev/null
+++ b/src/core/SkBlendModePriv.h
@@ -0,0 +1,19 @@
+/*
+ * Copyright 2016 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SkBlendModePriv_DEFINED
+#define SkBlendModePriv_DEFINED
+
+#include "SkBlendMode.h"
+
+bool SkBlendMode_SupportsCoverageAsAlpha(SkBlendMode);
+
+#if SK_SUPPORT_GPU
+sk_sp<GrXPFactory> SkBlendMode_AsXPFactory(SkBlendMode);
+#endif
+
+#endif