Add texture compression utility

src/utils/SkTextureCompressor.h

+/*
+ * 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_DEFINED
+#define SkTextureCompressor_DEFINED
+
+class SkBitmap;
+class SkData;
+
+namespace SkTextureCompressor {
+    // Various texture compression formats that we support.
+    enum Format {
+        // Alpha only format.
+        kLATC_Format,
+
+        kLast_Format = kLATC_Format
+    };
+    static const int kFormatCnt = kLast_Format + 1;
+
+    // Returns an SKData holding a blob of compressed data that corresponds

[robertphillips, 2014/06/09 19:50:18]

pixelConfig -> config ?

[krajcevski, 2014/06/09 20:39:34]

Done.

+    // to the bitmap. If pixelConfig is not a compressed format, then this
+    // function returns NULL. The returned SkData will have a refcount of one.
+    SkData *CompressBitmapToFormat(const SkBitmap &bitmap, Format config);
+}
+
+#endif