Add transport security state generator tests.

net/tools/transport_security_state_generator/trie/trie_bit_buffer.h

 // Copyright (c) 2016 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.
 
 #ifndef NET_TOOLS_TRANSPORT_SECURITY_STATE_GENERATOR_TRIE_TRIE_BIT_BUFFER_H_
 #define NET_TOOLS_TRANSPORT_SECURITY_STATE_GENERATOR_TRIE_TRIE_BIT_BUFFER_H_
 
 #include <stdint.h>
 
 #include <vector>
 
+#include "base/macros.h"
 #include "net/tools/transport_security_state_generator/huffman/huffman_builder.h"
 
 namespace net {
 
 namespace transport_security_state {
 
 class BitWriter;
 
 // TrieBitBuffer acts as a buffer for TrieWriter. It can be used to write bits,
 // characters, and positions. The characters are stored as their
@@ skipping 11 matching lines @@
   // buffer.
   void WriteBits(uint32_t bits, uint8_t number_of_bits);
 
   // Write a position to the buffer. Actually writes the difference between
   // |position| and |*last_position|. |*last_position| will be updated to equal
   // the input |position|.
   void WritePosition(uint32_t position, int32_t* last_position);
 
   // Writes the character in |byte| to the buffer using its Huffman
   // representation in |table|. Optionally tracks usage of the character in
-  // |*huffman_builder|.
-  void WriteChar(uint8_t byte,
+  // |*huffman_builder|. Returns false when |byte| is not found in |table|.
+  bool WriteChar(uint8_t byte,
                  const HuffmanRepresentationTable& table,
                  HuffmanBuilder* huffman_builder);
 
   // Writes the entire buffer to |*writer|. Returns the position |*writer| was
   // at before the buffer was written to it.
   uint32_t WriteToBitWriter(BitWriter* writer);
 
-  // Appends the buffered bits in |current_byte_| to |elements_|. Empty bits
-  // are filled with zero's.
+  // Appends the buffered bits in |current_byte_| to |elements_|. No padding
+  // will occur.
   void Flush();
 
  private:
   // Represents either the |number_of_bits| least-significant bits in |bits| or
   // a position (offset) in the trie.
   struct BitsOrPosition {
     uint8_t bits;
     uint8_t number_of_bits;
     uint32_t position;
   };
 
   // Returns the minimum number of bits needed to represent |input|.
   uint8_t BitLength(uint32_t input) const;
 
   // Append a new element to |elements_|.
   void AppendBitsElement(uint8_t bits, uint8_t number_of_bits);
   void AppendPositionElement(uint32_t position);
 
   // Buffers bits until they fill a whole byte.
   uint8_t current_byte_ = 0;
 
   // The number of bits currently in |current_byte_|.
   uint32_t used_ = 0;
 
   std::vector<BitsOrPosition> elements_;
+
+  DISALLOW_COPY_AND_ASSIGN(TrieBitBuffer);
 };
 
 }  // namespace transport_security_state
 
 }  // namespace net
 
 #endif  // NET_TOOLS_TRANSPORT_SECURITY_STATE_GENERATOR_TRIE_TRIE_BIT_BUFFER_H_