Add texture compression interface and ETC1 encoder.

cc/resources/texture_compress/texture_compressor.cc

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "cc/resources/texture_compress/texture_compressor.h"
+
+#include "base/logging.h"
+#include "cc/resources/texture_compress/texture_compressor_etc1.h"
+
+namespace cc {
+
+scoped_ptr<TextureCompressor> TextureCompressor::Create(Format format) {
+  switch (format) {
+    case kFormatETC1:
+      return make_scoped_ptr(new TextureCompressorETC1());
+  }
+
+  NOTREACHED();
+  return nullptr;
+}
+
+}  // namespace cc