Fix "value possibly truncated" warnings on MSVC, net/spdy/ edition.

net/spdy/hpack_huffman_table.h

 // Copyright 2014 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_SPDY_HPACK_HUFFMAN_TABLE_H_
 #define NET_SPDY_HPACK_HUFFMAN_TABLE_H_
 
 #include <cstddef>
 #include <string>
 #include <vector>
@@ skipping 49 matching lines @@
     // Returns |1 << indexed_length|.
     size_t size() const;
   };
 
   HpackHuffmanTable();
   ~HpackHuffmanTable();
 
   // Prepares HpackHuffmanTable to encode & decode the canonical Huffman
   // code as determined by the given symbols. Must be called exactly once.
   // Returns false if the input symbols define an invalid coding, and true
-  // otherwise. Symbols must be presented in ascending ID order with no gaps.
+  // otherwise. Symbols must be presented in ascending ID order with no gaps,
+  // and |symbol_count| must fit in a uint16.
   bool Initialize(const Symbol* input_symbols, size_t symbol_count);
 
   // Returns whether Initialize() has been successfully called.
   bool IsInitialized() const;
 
   // Encodes the input string to the output stream using the table's Huffman
   // context.
   void EncodeString(base::StringPiece in, HpackOutputStream* out) const;
 
   // Returns the encoded size of the input string.
@@ skipping 36 matching lines @@
   uint8 pad_bits_;
 
   // If initialization fails, preserve the symbol ID which failed validation
   // for examination in tests.
   uint16 failed_symbol_id_;
 };
 
 }  // namespace net
 
 #endif  // NET_SPDY_HPACK_HUFFMAN_TABLE_H_