Roll libwebp to 0.6.1

Bug: oss-fuzz:6299
Change-Id: I2e87368e04ff37db7e431fd1960f0bf91440037f
Reviewed-on: https://skia-review.googlesource.com/107281
Reviewed-by: Mike Klein <mtklein@chromium.org>
Commit-Queue: Kevin Lubick <kjlubick@google.com>
diff --git a/DEPS b/DEPS
index 7d9c245..c6f0cb8 100644
--- a/DEPS
+++ b/DEPS
@@ -14,7 +14,7 @@
   "third_party/externals/jsoncpp"       : "https://chromium.googlesource.com/external/github.com/open-source-parsers/jsoncpp.git@1.0.0",
   "third_party/externals/libjpeg-turbo" : "https://skia.googlesource.com/external/github.com/libjpeg-turbo/libjpeg-turbo.git@1.5.3",
   "third_party/externals/libpng"        : "https://skia.googlesource.com/third_party/libpng.git@v1.6.33",
-  "third_party/externals/libwebp"       : "https://chromium.googlesource.com/webm/libwebp.git@v0.6.0",
+  "third_party/externals/libwebp"       : "https://chromium.googlesource.com/webm/libwebp.git@v0.6.1",
   "third_party/externals/lua"           : "https://skia.googlesource.com/external/github.com/lua/lua.git@v5-3-4",
   "third_party/externals/microhttpd"    : "https://android.googlesource.com/platform/external/libmicrohttpd@748945ec6f1c67b7efc934ab0808e1d32f2fb98d",
   "third_party/externals/piex"          : "https://android.googlesource.com/platform/external/piex.git@8f540f64b6c170a16fb7e6e52d61819705c1522a",