local call masks errors in subshells

In another "things from the man page"

   The return status is 0 unless local is used outside a function, an
   invalid name is supplied, or name is a readonly variable.

Thus if anything fails in "cmd" of "local foo=$( cmd )" we don't
notice.

Change-Id: I22b10d5d39f014b6c92d2e101b167cbacf81afca

functions-common

@@ -684,9 +684,10 @@ function policy_add {
 # Gets or creates a domain
 # Usage: get_or_create_domain <name> <description>
 function get_or_create_domain {
+    local domain_id
     local os_url="$KEYSTONE_SERVICE_URI_V3"
     # Gets domain id
-    local domain_id=$(
+    domain_id=$(
         # Gets domain id
         openstack --os-token=$OS_TOKEN --os-url=$os_url \
             --os-identity-api-version=3 domain show $1 \
@@ -705,8 +706,9 @@ function get_or_create_domain {
 function get_or_create_group {
     local desc="${3:-}"
     local os_url="$KEYSTONE_SERVICE_URI_V3"
+    local group_id
     # Gets group id
-    local group_id=$(
+    group_id=$(
         # Creates new group with --or-show
         openstack --os-token=$OS_TOKEN --os-url=$os_url \
             --os-identity-api-version=3 group create $1 \
@@ -719,13 +721,14 @@ function get_or_create_group {
 # Gets or creates user
 # Usage: get_or_create_user <username> <password> <domain> [<email>]
 function get_or_create_user {
+    local user_id
     if [[ ! -z "$4" ]]; then
         local email="--email=$4"
     else
         local email=""
     fi
     # Gets user id
-    local user_id=$(
+    user_id=$(
         # Creates new user with --or-show
         openstack user create \
             $1 \
@@ -743,7 +746,8 @@ function get_or_create_user {
 # Gets or creates project
 # Usage: get_or_create_project <name> <domain>
 function get_or_create_project {
-    local project_id=$(
+    local project_id
+    project_id=$(
         # Creates new project with --or-show
         openstack --os-url=$KEYSTONE_SERVICE_URI_V3 \
             --os-identity-api-version=3 \
@@ -757,7 +761,8 @@ function get_or_create_project {
 # Gets or creates role
 # Usage: get_or_create_role <name>
 function get_or_create_role {
-    local role_id=$(
+    local role_id
+    role_id=$(
         # Creates role with --or-show
         openstack role create $1 \
             --os-url=$KEYSTONE_SERVICE_URI_V3 \
@@ -770,8 +775,9 @@ function get_or_create_role {
 # Gets or adds user role to project
 # Usage: get_or_add_user_project_role <role> <user> <project>
 function get_or_add_user_project_role {
+    local user_role_id
     # Gets user role id
-    local user_role_id=$(openstack role list \
+    user_role_id=$(openstack role list \
         --user $2 \
         --os-url=$KEYSTONE_SERVICE_URI_V3 \
         --os-identity-api-version=3 \
@@ -795,8 +801,9 @@ function get_or_add_user_project_role {
 # Gets or adds group role to project
 # Usage: get_or_add_group_project_role <role> <group> <project>
 function get_or_add_group_project_role {
+    local group_role_id
     # Gets group role id
-    local group_role_id=$(openstack role list \
+    group_role_id=$(openstack role list \
         --os-url=$KEYSTONE_SERVICE_URI_V3 \
         --os-identity-api-version=3 \
         --group $2 \
@@ -822,8 +829,9 @@ function get_or_add_group_project_role {
 # Gets or creates service
 # Usage: get_or_create_service <name> <type> <description>
 function get_or_create_service {
+    local service_id
     # Gets service id
-    local service_id=$(
+    service_id=$(
         # Gets service id
         openstack service show $2 -f value -c id 2>/dev/null ||
         # Creates new service if not exists
@@ -841,7 +849,8 @@ function get_or_create_service {
 # Create an endpoint with a specific interface
 # Usage: _get_or_create_endpoint_with_interface <service> <interface> <url> <region>
 function _get_or_create_endpoint_with_interface {
-    local endpoint_id=$(openstack endpoint list \
+    local endpoint_id
+    endpoint_id=$(openstack endpoint list \
         --os-url $KEYSTONE_SERVICE_URI_V3 \
         --os-identity-api-version=3 \
         --service $1 \