Display nicely formatted phone numbers

In conversation headers and as titles for contacts with no name. Updated
tests accordingly.

// FREEBIE

js/models/conversations.js

@@ -223,18 +223,28 @@
 
     getTitle: function() {
         if (this.isPrivate()) {
-            return this.get('name') || this.id;
+            return this.get('name') || this.getNumber();
         } else {
             return this.get('name') || 'Unknown group';
         }
     },
 
     getNumber: function() {
-        if (this.isPrivate()) {
-            return this.id;
-        } else {
+        if (!this.isPrivate()) {
             return '';
         }
+        var number = this.id;
+        try {
+            var parsedNumber = libphonenumber.parse(number);
+            var regionCode = libphonenumber.getRegionCodeForNumber(parsedNumber);
+            if (regionCode === storage.get('regionCode')) {
+                return libphonenumber.format(parsedNumber, libphonenumber.PhoneNumberFormat.NATIONAL);
+            } else {
+                return libphonenumber.format(parsedNumber, libphonenumber.PhoneNumberFormat.INTERNATIONAL);
+            }
+        } catch (e) {
+            return number;
+        }
     },
 
     isPrivate: function() {

test/models/conversations_test.js

@@ -123,7 +123,7 @@
         it('has a title', function() {
             var convos = new Whisper.ConversationCollection();
             var convo = convos.add(attributes);
-            assert.equal(convo.getTitle(), convo.id);
+            assert.equal(convo.getTitle(), '+1 808-555-5555');
 
             convo = convos.add({type: ''});
             assert.equal(convo.getTitle(), 'Unknown group');
@@ -135,7 +135,7 @@
         it('returns the number', function() {
             var convos = new Whisper.ConversationCollection();
             var convo = convos.add(attributes);
-            assert.equal(convo.getNumber(), convo.id);
+            assert.equal(convo.getNumber(), '+1 808-555-5555');
 
             convo = convos.add({type: ''});
             assert.equal(convo.getNumber(), '');