libwebp: update to 0.4.1

third_party/libwebp/utils/huffman.h

Index: third_party/libwebp/utils/huffman.h
diff --git a/third_party/libwebp/utils/huffman.h b/third_party/libwebp/utils/huffman.h
index e8afd27f24468a931d8d94058d8c71e5f42f7108..624bc1750b4429f98065554ae822d259580582a8 100644
--- a/third_party/libwebp/utils/huffman.h
+++ b/third_party/libwebp/utils/huffman.h
@@ -15,6 +15,7 @@
 #define WEBP_UTILS_HUFFMAN_H_
 
 #include <assert.h>
+#include "../webp/format_constants.h"
 #include "../webp/types.h"
 
 #ifdef __cplusplus
@@ -42,6 +43,12 @@ struct HuffmanTree {
   int num_nodes_;           // number of currently occupied nodes
 };
 
+// Huffman Tree group.
+typedef struct HTreeGroup HTreeGroup;
+struct HTreeGroup {
+  HuffmanTree htrees_[HUFFMAN_CODES_PER_META_CODE];
+};
+
 // Returns true if the given node is not a leaf of the Huffman tree.
 static WEBP_INLINE int HuffmanTreeNodeIsNotLeaf(
     const HuffmanTreeNode* const node) {
@@ -56,29 +63,37 @@ static WEBP_INLINE const HuffmanTreeNode* HuffmanTreeNextNode(
 
 // Releases the nodes of the Huffman tree.
 // Note: It does NOT free 'tree' itself.
-void HuffmanTreeRelease(HuffmanTree* const tree);
+void VP8LHuffmanTreeFree(HuffmanTree* const tree);
+
+// Creates the instance of HTreeGroup with specified number of tree-groups.
+HTreeGroup* VP8LHtreeGroupsNew(int num_htree_groups);
+
+// Releases the memory allocated for HTreeGroup.
+void VP8LHtreeGroupsFree(HTreeGroup* htree_groups, int num_htree_groups);
 
 // Builds Huffman tree assuming code lengths are implicitly in symbol order.
+// The 'huff_codes' and 'code_lengths' are pre-allocated temporary memory
+// buffers, used for creating the huffman tree.
 // Returns false in case of error (invalid tree or memory error).
-int HuffmanTreeBuildImplicit(HuffmanTree* const tree,
-                             const int* const code_lengths,
-                             int code_lengths_size);
+int VP8LHuffmanTreeBuildImplicit(HuffmanTree* const tree,
+                                 const int* const code_lengths,
+                                 int* const huff_codes,
+                                 int code_lengths_size);
 
 // Build a Huffman tree with explicitly given lists of code lengths, codes
 // and symbols. Verifies that all symbols added are smaller than max_symbol.
 // Returns false in case of an invalid symbol, invalid tree or memory error.
-int HuffmanTreeBuildExplicit(HuffmanTree* const tree,
-                             const int* const code_lengths,
-                             const int* const codes,
-                             const int* const symbols, int max_symbol,
-                             int num_symbols);
+int VP8LHuffmanTreeBuildExplicit(HuffmanTree* const tree,
+                                 const int* const code_lengths,
+                                 const int* const codes,
+                                 const int* const symbols, int max_symbol,
+                                 int num_symbols);
 
 // Utility: converts Huffman code lengths to corresponding Huffman codes.
 // 'huff_codes' should be pre-allocated.
 // Returns false in case of error (memory allocation, invalid codes).
-int HuffmanCodeLengthsToCodes(const int* const code_lengths,
-                              int code_lengths_size, int* const huff_codes);
-
+int VP8LHuffmanCodeLengthsToCodes(const int* const code_lengths,
+                                  int code_lengths_size, int* const huff_codes);
 
 #ifdef __cplusplus
 }    // extern "C"