libwebp: update to v0.5.1

third_party/libwebp/enc/picture_csp.c

Index: third_party/libwebp/enc/picture_csp.c
diff --git a/third_party/libwebp/enc/picture_csp.c b/third_party/libwebp/enc/picture_csp.c
index 0ef5f9eee2921d1b7355dbd6fd4d3684876f7fe4..607a6240b04541c242a19ade3b7113e989d33b86 100644
--- a/third_party/libwebp/enc/picture_csp.c
+++ b/third_party/libwebp/enc/picture_csp.c
@@ -1125,32 +1125,44 @@ static int Import(WebPPicture* const picture,
 
 int WebPPictureImportRGB(WebPPicture* picture,
                          const uint8_t* rgb, int rgb_stride) {
-  return (picture != NULL) ? Import(picture, rgb, rgb_stride, 3, 0, 0) : 0;
+  return (picture != NULL && rgb != NULL)
+             ? Import(picture, rgb, rgb_stride, 3, 0, 0)
+             : 0;
 }
 
 int WebPPictureImportBGR(WebPPicture* picture,
                          const uint8_t* rgb, int rgb_stride) {
-  return (picture != NULL) ? Import(picture, rgb, rgb_stride, 3, 1, 0) : 0;
+  return (picture != NULL && rgb != NULL)
+             ? Import(picture, rgb, rgb_stride, 3, 1, 0)
+             : 0;
 }
 
 int WebPPictureImportRGBA(WebPPicture* picture,
                           const uint8_t* rgba, int rgba_stride) {
-  return (picture != NULL) ? Import(picture, rgba, rgba_stride, 4, 0, 1) : 0;
+  return (picture != NULL && rgba != NULL)
+             ? Import(picture, rgba, rgba_stride, 4, 0, 1)
+             : 0;
 }
 
 int WebPPictureImportBGRA(WebPPicture* picture,
                           const uint8_t* rgba, int rgba_stride) {
-  return (picture != NULL) ? Import(picture, rgba, rgba_stride, 4, 1, 1) : 0;
+  return (picture != NULL && rgba != NULL)
+             ? Import(picture, rgba, rgba_stride, 4, 1, 1)
+             : 0;
 }
 
 int WebPPictureImportRGBX(WebPPicture* picture,
                           const uint8_t* rgba, int rgba_stride) {
-  return (picture != NULL) ? Import(picture, rgba, rgba_stride, 4, 0, 0) : 0;
+  return (picture != NULL && rgba != NULL)
+             ? Import(picture, rgba, rgba_stride, 4, 0, 0)
+             : 0;
 }
 
 int WebPPictureImportBGRX(WebPPicture* picture,
                           const uint8_t* rgba, int rgba_stride) {
-  return (picture != NULL) ? Import(picture, rgba, rgba_stride, 4, 1, 0) : 0;
+  return (picture != NULL && rgba != NULL)
+             ? Import(picture, rgba, rgba_stride, 4, 1, 0)
+             : 0;
 }
 
 //------------------------------------------------------------------------------