Bug 1491907 - Get comm/ version from comm/mail/*version.txt r=dustin

The release-update-verify-config task requires that the versions passed
to it match up with what's been released. The version of Thunderbird
does not necessarily match the Gecko version it's based on.

Depends on D6509

Differential Revision: https://phabricator.services.mozilla.com/D6510

taskcluster/taskgraph/parameters.py

@@ -6,7 +6,7 @@
 
 from __future__ import absolute_import, print_function, unicode_literals
 
-import functools
+import os.path
 import json
 import time
 import yaml
@@ -15,7 +15,7 @@ from datetime import datetime
 from mozbuild.util import ReadOnlyDict, memoize
 from mozversioncontrol import get_repository_object
 
-from . import APP_VERSION_PATH, GECKO, VERSION_PATH
+from . import GECKO
 from .util.attributes import RELEASE_PROJECTS
 
 
@@ -34,8 +34,16 @@ def get_contents(path):
     return contents
 
 
-get_version = functools.partial(get_contents, VERSION_PATH)
-get_app_version = functools.partial(get_contents, APP_VERSION_PATH)
+def get_version(product_dir='browser'):
+    version_path = os.path.join(GECKO, product_dir, 'config',
+                                'version_display.txt')
+    return get_contents(version_path)
+
+
+def get_app_version(product_dir='browser'):
+    app_version_path = os.path.join(GECKO, product_dir, 'config',
+                                    'version.txt')
+    return get_contents(app_version_path)
 
 
 # Please keep this list sorted and in sync with taskcluster/docs/parameters.rst