libwebp: update to 0.5.0

third_party/libwebp/dec/buffer.c

Index: third_party/libwebp/dec/buffer.c
diff --git a/third_party/libwebp/dec/buffer.c b/third_party/libwebp/dec/buffer.c
index 2129312fd6015ff13749f7efce1b5fe3770d79ce..9ed2b3fe1a5f7c09c95c18f64b2b821bb85232b8 100644
--- a/third_party/libwebp/dec/buffer.c
+++ b/third_party/libwebp/dec/buffer.c
@@ -189,11 +189,14 @@ VP8StatusCode WebPAllocateDecBuffer(int w, int h,
       h = ch;
     }
     if (options->use_scaling) {
-      if (options->scaled_width <= 0 || options->scaled_height <= 0) {
+      int scaled_width = options->scaled_width;
+      int scaled_height = options->scaled_height;
+      if (!WebPRescalerGetScaledDimensions(
+              w, h, &scaled_width, &scaled_height)) {
         return VP8_STATUS_INVALID_PARAM;
       }
-      w = options->scaled_width;
-      h = options->scaled_height;
+      w = scaled_width;
+      h = scaled_height;
     }
   }
   out->width = w;
@@ -203,12 +206,10 @@ VP8StatusCode WebPAllocateDecBuffer(int w, int h,
   status = AllocateBuffer(out);
   if (status != VP8_STATUS_OK) return status;
 
-#if WEBP_DECODER_ABI_VERSION > 0x0203
   // Use the stride trick if vertical flip is needed.
   if (options != NULL && options->flip) {
     status = WebPFlipBuffer(out);
   }
-#endif
   return status;
 }