Update libwebp to 0.4.0

third_party/libwebp/enc/token.c

Index: third_party/libwebp/enc/token.c
diff --git a/third_party/libwebp/enc/token.c b/third_party/libwebp/enc/token.c
index 6a63371f71e90e81d1cc4dc8060aa8efd3eee6ba..e696642f168a60b198a5b0e6ce2451cf8fbbf3a9 100644
--- a/third_party/libwebp/enc/token.c
+++ b/third_party/libwebp/enc/token.c
@@ -20,12 +20,9 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include "./cost.h"
 #include "./vp8enci.h"
 
-#if defined(__cplusplus) || defined(c_plusplus)
-extern "C" {
-#endif
-
 #if !defined(DISABLE_TOKEN_BUFFER)
 
 // we use pages to reduce the number of memcpy()
@@ -238,6 +235,29 @@ int VP8EmitTokens(VP8TBuffer* const b, VP8BitWriter* const bw,
   return 1;
 }
 
+// Size estimation
+size_t VP8EstimateTokenSize(VP8TBuffer* const b, const uint8_t* const probas) {
+  size_t size = 0;
+  const VP8Tokens* p = b->pages_;
+  if (b->error_) return 0;
+  while (p != NULL) {
+    const VP8Tokens* const next = p->next_;
+    const int N = (next == NULL) ? b->left_ : 0;
+    int n = MAX_NUM_TOKEN;
+    while (n-- > N) {
+      const uint16_t token = p->tokens_[n];
+      const int bit = token & (1 << 15);
+      if (token & FIXED_PROBA_BIT) {
+        size += VP8BitCost(bit, token & 0xffu);
+      } else {
+        size += VP8BitCost(bit, probas[token & 0x3fffu]);
+      }
+    }
+    p = next;
+  }
+  return size;
+}
+
 //------------------------------------------------------------------------------
 
 #else     // DISABLE_TOKEN_BUFFER
@@ -251,6 +271,3 @@ void VP8TBufferClear(VP8TBuffer* const b) {
 
 #endif    // !DISABLE_TOKEN_BUFFER
 
-#if defined(__cplusplus) || defined(c_plusplus)
-}    // extern "C"
-#endif