Bug 1021478 - [Dialer] Call on the last used SIM for this contact/number when hitting the Bluetooth call button. r=Rik
Merge pull request #22181 from DouglasSherk/1021478-dialer-bluetooth-call

Bug 1021478 - [Dialer] Call on the last used SIM for this contact/number when hitting the Bluetooth call button. r=Rik
Bug 944249 - [Messages] move the segment information request and size check and message type handling to compose.js r=schung

* adds a MessageManager.getSegmentInfo function
* ThreadUI sends a recipientschange event when recipients change
* Compose sends a new event "segmentinfo" when that info changes
* various other refactoring changes in Compose
Bug 944249 - Follow-up: Don't update the segment info when we merely change the subject
Bug 944249 - Follow-ups:

* rename some test titles
* do not initialize recipients in MockThreadUI if we don't have the templating node
* assert that we reject the promise returned by getSegmentInfo with a proper
  Error when mozMobileMessage is absent