playground: update NaCl to trunk.544461

This pulls in, which fixes the
underlying issue of NaCl mishandling signals during a SIGSEGV.

Fixes golang/go#23836

Change-Id: I562909354ee0e2aec819b9f7116f86f673ccadff
Reviewed-by: Andrew Bonventre <>
diff --git a/Dockerfile b/Dockerfile
index ddec475..a1fd7c4 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -19,7 +19,7 @@
 RUN set -x && \
     apt-get update && apt-get install -y ${BUILD_DEPS} ${DEPS} --no-install-recommends && rm -rf /var/lib/apt/lists/*
-RUN curl -s | tar -xj -C /usr/local/bin --strip-components=2 pepper_49/tools/sel_ldr_x86_64
+RUN curl -s | tar -xj -C /usr/local/bin --strip-components=2 pepper_67/tools/sel_ldr_x86_64
 # Get the Go binary.
 RUN curl -sSL$GO_VERSION.linux-amd64.tar.gz -o /tmp/go.tar.gz && \