fix cross-shard merges that copy retired sms communication channels

test plan:
 * add an sms channel to a user
 * retire that channel
 * merge that user with a user in a different shard

Change-Id: Ibd24978c7456505b813961044b635b99b6beec6b
Reviewed-on: https://gerrit.instructure.com/15318
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: Brian Palmer <brianp@instructure.com>

app/models/communication_channel.rb

@@ -35,7 +35,7 @@ class CommunicationChannel < ActiveRecord::Base
   before_save :consider_building_pseudonym
   validates_presence_of :path
   validate :uniqueness_of_path
-  validate :not_otp_communication_channel, :if => lambda { |cc| cc.path_type == TYPE_SMS && cc.retired? }
+  validate :not_otp_communication_channel, :if => lambda { |cc| cc.path_type == TYPE_SMS && cc.retired? && !cc.new_record? }
 
   acts_as_list :scope => :user_id
   

spec/models/user_spec.rb

@@ -829,6 +829,22 @@ describe User do
             ['o@instructure.com', 'retired']
         ]
       end
+
+      it "should not fail copying retired sms channels" do
+        @user1 = User.create!
+        @shard1.activate do
+          @user2 = User.create!
+        end
+
+        @cc = @user2.communication_channels.sms.create!(:path => 'abc')
+        @cc.retire!
+
+        @user2.move_to_user(@user1)
+        @user1.communication_channels.reload.length.should == 1
+        cc = @user1.communication_channels.first
+        cc.path.should == 'abc'
+        cc.workflow_state.should == 'retired'
+      end
     end
   end