Undo the work done to switch from ondrej to mysql's apt repo

We will use the community PPA for 12.04
Ondrej's PPA for 16.04

Even if the community PPA releases 5.6 packages, we're unlikely to
switch back on 16.04.  We'll just work towards 5.7 which are included
natively in 16.04.

playbooks/roles/mysql/defaults/main.yml

 ---
-remove_experimental_mysql: false
-
 mysql_debian_pkgs:
   - "mysql-server-5.6"
   - python-mysqldb
-  

playbooks/roles/mysql/tasks/main.yml

 ---
-- name: Look for mysql 5.6
-  shell: "dpkg -s mysql-server"
-  ignore_errors: yes
-  register: mysql_56_installed
-  changed_when: no
+# TODO remove after we release a 16.04 Devstack
+- name: Add MySQL community apt key
+  apt_key:
+    id: 8C718D3B5072E1F5
+    keyserver: "{{ COMMON_EDX_PPA_KEY_SERVER }}"
+    state: present
+  when: ansible_distribution_release == 'precise'
 
-- name: Important message
-  debug:
-    msg: |
-      "MySQL experimental is already installed, make 'remove_experimental_mysql: true' in defaults/main.yml, 
-      if you want to remove it and install the stable version of MySQL"
-  when: "'5.6.14' in  mysql_56_installed.stdout and not remove_experimental_mysql"
+# TODO remove after we release a 16.04 Devstack
+# Despite ondrej's ppa having 12.04 support, we would need to do shenanigans and uninstalling
+# to switch back cleanly without publishing a new base devstack box.  Easier to just clean this
+# up with Ficus.
+- name: Install MySQL from their community PPA
+  apt_repository:
+    repo: "deb http://repo.mysql.com/apt/ubuntu/ precise mysql-5.6"
+    update_cache: yes
+  when: ansible_distribution_release == 'precise'
 
-- pause:
-    seconds: 10
-  when: "'5.6.14' in  mysql_56_installed.stdout and not remove_experimental_mysql"
+# repo.mysql.com does not have 5.6 packages for xenial
+- name: Install MySQL from ondrej PPA
+  apt_repository:
+    repo: "ppa:ondrej/mysql-5.6"
+    update_cache: yes
+  when: ansible_distribution_release == 'xenial'
 
-# remove this, once the new devstack is out
-- include: remove_mysql_experimental.yml
-  when: remove_experimental_mysql
+- name: Install mysql-5.6 and dependencies
+  apt: 
+    name: "{{ item }}" 
+    install_recommends: yes
+    state: present
+  with_items: mysql_debian_pkgs
 
-- include: mysql.yml
-  when: (mysql_56_installed.rc == 1) or (remove_experimental_mysql)
\ No newline at end of file
+- name: Start mysql
+  service: 
+    name: mysql 
+    state: started
+
+- name: Ensure Anonymous user(s) does not exist
+  mysql_user: 
+    name: '' 
+    host: "{{ item }}" 
+    state: absent
+  with_items:
+    - localhost
+    - "{{ ansible_hostname }}"

playbooks/roles/mysql/tasks/mysql.yml

----
-# Here are the few steps that I have performed to get the `debconf` setting information:
-#
-# - downloaded the mysql-apt-repo from the mysql official site(named: mysql-apt-config_0.6.0-1_all.deb)
-# - Find the `debconf` setting information after installing this `deb` package
-# 
-# # debconf-show mysql-apt-config
-# * mysql-apt-config/select-server: mysql-5.6
-#   mysql-apt-config/unsupported-platform: abort
-#   mysql-apt-config/repo-codename: precise
-# * mysql-apt-config/select-product: Apply
-#   mysql-apt-config/select-tools:
-#   mysql-apt-config/repo-distro: ubuntu
-# 
-# - Even to get more information about the `debconf` options of the package:
-# 
-# # debconf-get-selections|grep mysql-apt-config
-# mysql-apt-config  mysql-apt-config/select-server  select  mysql-5.6
-# mysql-apt-config  mysql-apt-config/unsupported-platform select  abort
-# mysql-apt-config  mysql-apt-config/repo-codename  select  precise
-# mysql-apt-config  mysql-apt-config/select-product select  Apply
-# mysql-apt-config  mysql-apt-config/select-tools select
-# mysql-apt-config  mysql-apt-config/repo-distro  select  ubuntu
-# 
-# - After the installation, I have checked the `/etc/apt/sources.list.d` directory and found one file `mysql.list` 
-# with following contents:
-# 
-# deb http://repo.mysql.com/apt/ubuntu/ precise mysql-apt-config
-# deb http://repo.mysql.com/apt/ubuntu/ precise mysql-5.6
-# deb-src http://repo.mysql.com/apt/ubuntu/ precise mysql-5.6
-# 
-#
-# Thought that instead of performing all those steps and get the repo, why not directly use this repo 
-# `deb http://repo.mysql.com/apt/ubuntu/ precise mysql-5.6`, I just picked this line and directly used it and it worked for us. 
-
-- name: Add MySQL community apt key
-  apt_key:
-    id: 8C718D3B5072E1F5
-    keyserver: "{{ COMMON_EDX_PPA_KEY_SERVER }}"
-    state: present
-  when: ansible_distribution_release == 'precise'
-
-# Despite ondrej's ppa having 12.04 support, we would need to do shenanigans and uninstalling
-# to switch back cleanly without publishing a new base devstack box.  Easier to just clean this
-# up with Ficus.
-- name: Install MySQL from their community PPA
-  apt_repository:
-    repo: "deb http://repo.mysql.com/apt/ubuntu/ precise mysql-5.6"
-    update_cache: yes
-  when: ansible_distribution_release == 'precise'
-
-# repo.mysql.com does not have 5.6 packages for xenial
-- name: Install MySQL from ondrej PPA
-  apt_repository:
-    repo: "ppa:ondrej/mysql-5.6"
-    update_cache: yes
-  when: ansible_distribution_release == 'xenial'
-
-- name: Install mysql-5.6 and dependencies
-  apt: 
-    name: "{{ item }}" 
-    install_recommends: yes
-    state: present
-  with_items: mysql_debian_pkgs
-
-- name: Start mysql
-  service: 
-    name: mysql 
-    state: started
-
-- name: Ensure Anonymous user(s) does not exist
-  mysql_user: 
-    name: '' 
-    host: "{{ item }}" 
-    state: absent
-  with_items:
-    - localhost
-    - "{{ ansible_hostname }}"

playbooks/roles/mysql/tasks/remove_mysql_experimental.yml

----
-- name: Stop mysql service
-  service: 
-    name: mysql 
-    state: stopped
-
-- name: Remove experimental apt repository
-  apt_repository:
-    repo: 'deb http://ppa.launchpad.net/ondrej/mysql-experimental/ubuntu precise main'
-    state: absent
-
-- name: Remove experimental version of mysql
-  apt: 
-    name: "{{ item }}" 
-    state: absent 
-    purge: yes
-  with_items:
-    - mysql-server-5.6
-    - mysql-server
\ No newline at end of file