fix(extensions):Fix extension method calls that weren't passing args hash

examples/N1-Quick-Schedule/lib/availability-composer-extension.coffee

@@ -7,7 +7,7 @@ class AvailabilityComposerExtension extends ComposerExtension
   # When subclassing the ComposerExtension, you can add your own custom logic
   # to execute before a draft is sent in the @finalizeSessionBeforeSending
   # method. Here, we're registering the events before we send the draft.
-  @finalizeSessionBeforeSending: (session) ->
+  @finalizeSessionBeforeSending: ({session}) ->
     body = session.draft().body
     participants = session.draft().participants()
     sender = session.draft().from

src/extensions/composer-extension.coffee

@@ -112,7 +112,7 @@ class ComposerExtension extends ContenteditableExtension
       session.changes.add(body: clean)
   ```
   ###
-  @finalizeSessionBeforeSending: (session) ->
+  @finalizeSessionBeforeSending: ({session}) ->
     return Promise.resolve(session)
 
 module.exports = ComposerExtension

src/flux/stores/draft-store.coffee

@@ -532,7 +532,7 @@ class DraftStore
   # Give third-party plugins an opportunity to sanitize draft data
   _runExtensionsBeforeSend: (session) =>
     Promise.each @extensions(), (ext) ->
-      ext.finalizeSessionBeforeSending(session)
+      ext.finalizeSessionBeforeSending({session})
     .return(session)
 
   _onRemoveFile: ({file, messageClientId}) =>