Issue #5012 - Add minimum_opera_version support to metadata.json

templates/manifest.json.tmpl

 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 {
   "manifest_version": 2,
   {%- if releaseBuild %}
   "name": "__MSG_name__",
   {%- else %}
   "name": "__MSG_name_devbuild__",
   {%- endif %}
 
   "short_name": "__MSG_name__",
   "description": "__MSG_description__",
   "default_locale": "en_US",
   "version": {{version|json}},
   "author": {{metadata.get('general', 'author')|json}},
 
   {%- if metadata.has_section('compat') and metadata.has_option('compat', 'chrome') %}
   "minimum_chrome_version": {{metadata.get('compat', 'chrome')|json}},
   {%- endif %}
 
+  {%- if metadata.has_section('compat') and metadata.has_option('compat', 'opera') %}
+  "minimum_opera_version": {{metadata.get('compat', 'opera')|json}},
+  {%- endif %}
+
   {%- if metadata.has_section('compat') and metadata.has_option('compat', 'edge') %}
   "minimum_edge_version": {{metadata.get('compat', 'edge')|json}},
   {%- endif %}
 
   {%- if type == 'gecko-webext' %}
   "applications":
   {
     "gecko":
     {
       "id": {{metadata.get('general', 'id')|json}}
@@ skipping 75 matching lines @@
   {%- endif %}
 
   {%- if metadata.has_option('general', 'managedStorageSchema') %}
   "storage": {
     "managed_schema": {{metadata.get('general', 'managedStorageSchema')|json}}
   },
   {%- endif %}
 
   "_dummy": false
 }