Added brotli enc/ and tools/ directories.

third_party/brotli/enc/block_splitter.h

Index: third_party/brotli/enc/block_splitter.h
diff --git a/third_party/brotli/enc/block_splitter.h b/third_party/brotli/enc/block_splitter.h
new file mode 100644
index 0000000000000000000000000000000000000000..4f69296808e4918949eb950ade0ece1a987c6fe2
--- /dev/null
+++ b/third_party/brotli/enc/block_splitter.h
@@ -0,0 +1,61 @@
+/* Copyright 2013 Google Inc. All Rights Reserved.
+
+   Distributed under MIT license.
+   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
+*/
+
+// Block split point selection utilities.
+
+#ifndef BROTLI_ENC_BLOCK_SPLITTER_H_
+#define BROTLI_ENC_BLOCK_SPLITTER_H_
+
+#include <vector>
+
+#include "./command.h"
+#include "./metablock.h"
+#include "./types.h"
+
+namespace brotli {
+
+struct BlockSplitIterator {
+  explicit BlockSplitIterator(const BlockSplit& split)
+      : split_(split), idx_(0), type_(0), length_(0) {
+    if (!split.lengths.empty()) {
+      length_ = split.lengths[0];
+    }
+  }
+
+  void Next(void) {
+    if (length_ == 0) {
+      ++idx_;
+      type_ = split_.types[idx_];
+      length_ = split_.lengths[idx_];
+    }
+    --length_;
+  }
+
+  const BlockSplit& split_;
+  size_t idx_;
+  size_t type_;
+  size_t length_;
+};
+
+void CopyLiteralsToByteArray(const Command* cmds,
+                             const size_t num_commands,
+                             const uint8_t* data,
+                             const size_t offset,
+                             const size_t mask,
+                             std::vector<uint8_t>* literals);
+
+void SplitBlock(const Command* cmds,
+                const size_t num_commands,
+                const uint8_t* data,
+                const size_t offset,
+                const size_t mask,
+                BlockSplit* literal_split,
+                BlockSplit* insert_and_copy_split,
+                BlockSplit* dist_split);
+
+}  // namespace brotli
+
+#endif  // BROTLI_ENC_BLOCK_SPLITTER_H_