libwebp: update to 0.5.0

third_party/libwebp/dec/tree.c

Index: third_party/libwebp/dec/tree.c
diff --git a/third_party/libwebp/dec/tree.c b/third_party/libwebp/dec/tree.c
index 31208d9d4cca3ff1ac8e8755a250913938afbda3..c2007ea733dd1ef926118b6f107fda26c1a1d6cf 100644
--- a/third_party/libwebp/dec/tree.c
+++ b/third_party/libwebp/dec/tree.c
@@ -494,6 +494,12 @@ static const uint8_t
 };
 
 // Paragraph 9.9
+
+static const int kBands[16 + 1] = {
+  0, 1, 2, 3, 6, 4, 5, 6, 6, 6, 6, 6, 6, 6, 6, 7,
+  0  // extra entry as sentinel
+};
+
 void VP8ParseProba(VP8BitReader* const br, VP8Decoder* const dec) {
   VP8Proba* const proba = &dec->proba_;
   int t, b, c, p;
@@ -507,6 +513,9 @@ void VP8ParseProba(VP8BitReader* const br, VP8Decoder* const dec) {
         }
       }
     }
+    for (b = 0; b < 16 + 1; ++b) {
+      proba->bands_ptr_[t][b] = &proba->bands_[t][kBands[b]];
+    }
   }
   dec->use_skip_proba_ = VP8Get(br);
   if (dec->use_skip_proba_) {