libwebp: update snapshot to v0.3.0-rc6

third_party/libwebp/enc/syntax.c

Index: third_party/libwebp/enc/syntax.c
diff --git a/third_party/libwebp/enc/syntax.c b/third_party/libwebp/enc/syntax.c
index 7c8c7b1a848123443938e8417cd884861d6454c8..24e008c3d89db630bc206d882102c2d40e730216 100644
--- a/third_party/libwebp/enc/syntax.c
+++ b/third_party/libwebp/enc/syntax.c
@@ -11,7 +11,9 @@
 
 #include <assert.h>
 
-#include "../webp/format_constants.h"
+#include "../utils/utils.h"
+#include "../webp/format_constants.h"  // RIFF constants
+#include "../webp/mux_types.h"         // ALPHA_FLAG
 #include "./vp8enci.h"
 
 #if defined(__cplusplus) || defined(c_plusplus)
@@ -21,18 +23,6 @@ extern "C" {
 //------------------------------------------------------------------------------
 // Helper functions
 
-// TODO(later): Move to webp/format_constants.h?
-static void PutLE24(uint8_t* const data, uint32_t val) {
-  data[0] = (val >>  0) & 0xff;
-  data[1] = (val >>  8) & 0xff;
-  data[2] = (val >> 16) & 0xff;
-}
-
-static void PutLE32(uint8_t* const data, uint32_t val) {
-  PutLE24(data, val);
-  data[3] = (val >> 24) & 0xff;
-}
-
 static int IsVP8XNeeded(const VP8Encoder* const enc) {
   return !!enc->has_alpha_;  // Currently the only case when VP8X is needed.
                              // This could change in the future.
@@ -73,7 +63,7 @@ static WebPEncodingError PutVP8XHeader(const VP8Encoder* const enc) {
   assert(pic->width <= MAX_CANVAS_SIZE && pic->height <= MAX_CANVAS_SIZE);
 
   if (enc->has_alpha_) {
-    flags |= ALPHA_FLAG_BIT;
+    flags |= ALPHA_FLAG;
   }
 
   PutLE32(vp8x + TAG_SIZE,              VP8X_CHUNK_SIZE);
@@ -327,7 +317,9 @@ static size_t GeneratePartition0(VP8Encoder* const enc) {
 
   PutSegmentHeader(bw, enc);
   PutFilterHeader(bw, &enc->filter_hdr_);
-  VP8PutValue(bw, enc->config_->partitions, 2);
+  VP8PutValue(bw, enc->num_parts_ == 8 ? 3 :
+                  enc->num_parts_ == 4 ? 2 :
+                  enc->num_parts_ == 2 ? 1 : 0, 2);
   PutQuant(bw, enc);
   VP8PutBitUniform(bw, 0);   // no proba update
   VP8WriteProbas(bw, &enc->proba_);