fix enabled parameter of update doesn't default to None

Currently, enabled parameter of v3.domains.update and v3.regions.update
defaults to True. It is easy to make mistakes and difficult to use.

Closes-Bug: #1413071
Change-Id: I8b392ff228691b2735b06747dcfb802d4c191a54

keystoneclient/tests/v3/test_domains.py

@@ -41,3 +41,8 @@ class DomainTests(utils.TestCase, utils.CrudTests):
         expected_query = {'enabled': '0'}
         super(DomainTests, self).test_list(expected_query=expected_query,
                                            enabled=False)
+
+    def test_update_enabled_defaults_to_none(self):
+        req_ref = self.new_ref()
+        del req_ref['enabled']
+        super(DomainTests, self).test_update(req_ref=req_ref)

keystoneclient/tests/v3/test_regions.py

@@ -31,3 +31,8 @@ class RegionTests(utils.TestCase, utils.CrudTests):
         kwargs.setdefault('enabled', True)
         kwargs.setdefault('id', uuid.uuid4().hex)
         return kwargs
+
+    def test_update_enabled_defaults_to_none(self):
+        req_ref = self.new_ref()
+        del req_ref['enabled']
+        super(RegionTests, self).test_update(req_ref=req_ref)

keystoneclient/v3/domains.py

@@ -60,7 +60,7 @@ class DomainManager(base.CrudManager):
 
     @utils.positional(enforcement=utils.positional.WARN)
     def update(self, domain, name=None,
-               description=None, enabled=True, **kwargs):
+               description=None, enabled=None, **kwargs):
         return super(DomainManager, self).update(
             domain_id=base.getid(domain),
             name=name,

keystoneclient/v3/regions.py

@@ -65,7 +65,7 @@ class RegionManager(base.CrudManager):
         return super(RegionManager, self).list(
             **kwargs)
 
-    def update(self, region, description=None, enabled=True,
+    def update(self, region, description=None, enabled=None,
                parent_region=None, **kwargs):
         """Update a Catalog region.
 
@@ -75,7 +75,7 @@ class RegionManager(base.CrudManager):
                 pre-existing region in the backend.  Allows for hierarchical
                 region organization.
             :param enabled: determines whether the endpoint appears in the
-                catalog. Defaults to True
+                catalog.
 
         """
         return super(RegionManager, self).update(