fix command curl ... line for osx

Author: k-okada

.travis.yml

@@ -86,7 +86,7 @@ before_install: # Use this to prepare the system to install prerequisites or dep
   - echo -e "Host github.com\n\tStrictHostKeyChecking no\n" >> ~/.ssh/config
   # use stable rvm to avoid "shell_session_update: command not found" error on OSX.
   # https://github.com/travis-ci/travis-ci/issues/6307
-  - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; command curl -sSL https://rvm.io/mpapis.asc | gpg --import -; then rvm get stable; fi
+  - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then set -x; gpg --version; gpg --keyserver hkp://keys.gnupg.net --recv-keys 409B6B1796C275462A1703113804BB82D39DC0E3 7D2BAF1CF37B13E2069D6956105BD0E739499BDB || command curl -sSL https://rvm.io/mpapis.asc | gpg --import -; rvm get stable; set +x; fi
   # Define some config vars
 install:
   - export CI_SOURCE_PATH=$(pwd)