Updates the Java Dockerfiles to pull source from GitHub

tools/dockerfile/grpc_java/Dockerfile

@@ -1,9 +1,6 @@
 # Dockerfile for the gRPC Java dev image
 FROM grpc/java_base
 
-# Start the daemon that allows access to private git-on-borg repos
-RUN /var/local/git/gcompute-tools/git-cookie-authdaemon
-
 RUN  cd /var/local/git/grpc-java/lib/okhttp && \
   mvn -pl okhttp -am install
 RUN  cd /var/local/git/grpc-java/lib/netty && \

tools/dockerfile/grpc_java_base/Dockerfile

@@ -20,14 +20,20 @@ ENV M2_HOME /var/local/apache-maven-3.2.1
 ENV PATH $PATH:$JAVA_HOME/bin:$M2_HOME/bin
 ENV LD_LIBRARY_PATH /usr/local/lib
 
-# Start the daemon that allows access to the protected git-on-borg repos
-RUN /var/local/git/gcompute-tools/git-cookie-authdaemon
+# Install a GitHub SSH service credential that gives access to the GitHub repo while it's private
+# TODO: remove this once the repo is public
+ADD .ssh .ssh
+RUN chmod 600 .ssh/github.rsa
+RUN mkdir -p $HOME/.ssh && echo 'Host github.com' > $HOME/.ssh/config
+RUN echo "    IdentityFile /.ssh/github.rsa" >> $HOME/.ssh/config
+RUN echo 'StrictHostKeyChecking no' >> $HOME/.ssh/config
 
-RUN git clone --recursive https://team.googlesource.com/one-platform-grpc-team/grpc-java /var/local/git/grpc-java
+# Get the source from GitHub
+RUN git clone --recursive git@github.com:google/grpc-java.git /var/local/git/grpc-java
 
 RUN cd /var/local/git/grpc-java/lib/okhttp && \
   mvn -pl okhttp -am validate
 RUN cd /var/local/git/grpc-java/lib/netty && \
   mvn -pl codec-http2 -am validate
 RUN cd /var/local/git/grpc-java && \
-  mvn validate
+  mvn validate