be opinionated: only use get-pip.py

get-pip.py is now on a CDN, and is the prefered way to get pip.

Remove the default path of using pip tarballs from pypi and use
get-pip.py on from here on.

Closes-Bug: #1326539

Change-Id: I0661f7c6913ba6b3e1d00b30e22740d150bfd060
diff --git a/tools/install_pip.sh b/tools/install_pip.sh
index 1eb9e7a..d3f5e78 100755
--- a/tools/install_pip.sh
+++ b/tools/install_pip.sh
@@ -24,28 +24,7 @@
 
 FILES=$TOP_DIR/files
 
-# Handle arguments
-
-USE_GET_PIP=${USE_GET_PIP:-0}
-INSTALL_PIP_VERSION=${INSTALL_PIP_VERSION:-"1.4.1"}
-while [[ -n "$1" ]]; do
-    case $1 in
-        --force)
-            FORCE=1
-            ;;
-        --pip-version)
-            INSTALL_PIP_VERSION="$2"
-            shift
-            ;;
-        --use-get-pip)
-            USE_GET_PIP=1;
-            ;;
-    esac
-    shift
-done
-
-PIP_GET_PIP_URL=https://raw.github.com/pypa/pip/master/contrib/get-pip.py
-PIP_TAR_URL=https://pypi.python.org/packages/source/p/pip/pip-$INSTALL_PIP_VERSION.tar.gz
+PIP_GET_PIP_URL=https://bootstrap.pypa.io/get-pip.py
 
 GetDistro
 echo "Distro: $DISTRO"
@@ -70,15 +49,6 @@
     sudo -E python $FILES/get-pip.py
 }
 
-function install_pip_tarball {
-    if [[ ! -r $FILES/pip-$INSTALL_PIP_VERSION.tar.gz ]]; then
-        (cd $FILES; \
-            curl -O $PIP_TAR_URL; \
-            tar xvfz pip-$INSTALL_PIP_VERSION.tar.gz 1>/dev/null)
-    fi
-    (cd $FILES/pip-$INSTALL_PIP_VERSION; \
-        sudo -E python setup.py install 1>/dev/null)
-}
 
 # Show starting versions
 get_versions
@@ -88,10 +58,6 @@
 # Eradicate any and all system packages
 uninstall_package python-pip
 
-if [[ "$USE_GET_PIP" == "1" ]]; then
-    install_get_pip
-else
-    install_pip_tarball
-fi
+install_get_pip
 
 get_versions