Refactor texture compressors into separate files

src/utils/SkTextureCompressor_R11EAC.h

Index: src/utils/SkTextureCompressor_R11EAC.h
diff --git a/src/utils/SkTextureCompressor_R11EAC.h b/src/utils/SkTextureCompressor_R11EAC.h
new file mode 100644
index 0000000000000000000000000000000000000000..5f981ef46f409754b32a39b907ecd9144740a74f
--- /dev/null
+++ b/src/utils/SkTextureCompressor_R11EAC.h
@@ -0,0 +1,21 @@
+/*
+ * Copyright 2014 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SkTextureCompressor_R11EAC_DEFINED
+#define SkTextureCompressor_R11EAC_DEFINED
+
+#include "SkBlitter.h"
+
+namespace SkTextureCompressor {
+
+    bool CompressA8ToR11EAC(uint8_t* dst, const uint8_t* src,
+                            int width, int height, int rowBytes);
+
+    SkBlitter* CreateR11EACBlitter(int width, int height, void* outputBuffer);
+}
+
+#endif  // SkTextureCompressor_R11EAC_DEFINED