Move grpc installation from docker file to script.
diff --git a/test/distrib/cpp/run_distrib_test.sh b/test/distrib/cpp/run_distrib_test.sh
index 7b6418d..5c21a1e 100755
--- a/test/distrib/cpp/run_distrib_test.sh
+++ b/test/distrib/cpp/run_distrib_test.sh
@@ -30,7 +30,13 @@
set -ex
-cd $EXTERNAL_GIT_ROOT
+git clone https://github.com/grpc/grpc.git
+cd grpc && git submodule update --init
+
+cd third_party/protobuf && ./autogen.sh && \
+./configure && make -j12 && make check && make install && ldconfig
+
+cd ../.. && make -j12 && make install
cd examples/cpp/helloworld
diff --git a/tools/dockerfile/distribtest/cpp_jessie_x64/Dockerfile b/tools/dockerfile/distribtest/cpp_jessie_x64/Dockerfile
index 4bbbddd..b02208f 100644
--- a/tools/dockerfile/distribtest/cpp_jessie_x64/Dockerfile
+++ b/tools/dockerfile/distribtest/cpp_jessie_x64/Dockerfile
@@ -42,12 +42,4 @@
pkg-config \
unzip && apt-get clean
-RUN git clone https://github.com/grpc/grpc.git
-RUN cd grpc && git submodule update --init
-
-RUN cd grpc/third_party/protobuf && ./autogen.sh && \
- ./configure && make -j12 && make check && make install && ldconfig
-
-RUN cd grpc && make -j12 && make install
-
CMD ["bash"]