Support for group-member verifications via second-level panel

Also:
- All the necessary wire-up to update things in real time. If you have
a safety number page up via a group member view as well as via a 1:1
conversation with that contact, they'll both be updated as the
underlying model changes. Similarly, the overall group will update
in real-time as members change.
- A bit of special-casing for yourself in a group conversation - you're
shown as 'me' and are not clickable, where normally that would take you
to the Safety Number screen for that contact. You are also not included
in the trust calculations for a given group.

FREEBIE

js/models/conversations.js

@@ -37,6 +37,8 @@
     },
 
     initialize: function() {
+        this.ourNumber = textsecure.storage.user.getNumber();
+
         this.contactCollection = new Backbone.Collection();
         this.messageCollection = new Whisper.MessageCollection([], {
             conversation: this
@@ -48,6 +50,84 @@
         this.on('destroy', this.revokeAvatarUrl);
     },
 
+    updateVerified: function() {
+        // TODO: replace this with the real call
+        function checkTrustStore() {
+            return Promise.resolve('default');
+        }
+
+        if (this.isPrivate()) {
+            return Promise.all([
+                checkTrustStore(this.id),
+                this.fetch()
+            ]).then(function(results) {
+                var trust = results[0];
+                return this.save({verified: trust});
+            });
+        } else {
+            return this.fetchContacts().then(function() {
+                return Promise.all(this.contactCollection.map(function(contact) {
+                    if (contact.id !== this.myNumber) {
+                        return contact.updateVerified();
+                    }
+                }.bind(this)));
+            }.bind(this));
+        }
+    },
+
+    isVerified: function() {
+        if (this.isPrivate()) {
+            return this.get('verified') === 'verified';
+        } else {
+            return this.contactCollection.every(function(contact) {
+                if (contact.id === this.myNumber) {
+                    return true;
+                } else {
+                    return contact.isVerified();
+                }
+            }.bind(this));
+        }
+    },
+    isConflict: function() {
+        if (this.isPrivate()) {
+            var verified = this.get('verified');
+            return verified !== 'verified' && verified !== 'default';
+        } else {
+            return Boolean(this.getConflicts().length);
+        }
+    },
+    getConflicts: function() {
+        if (this.isPrivate()) {
+            return this.isConflict() ? [this] : [];
+        } else {
+            return this.contactCollection.filter(function(contact) {
+                if (contact.id === this.myNumber) {
+                    return false;
+                } else {
+                    return contact.isConflict();
+                }
+            }.bind(this));
+        }
+    },
+    onMemberVerifiedChange: function() {
+        // If the verified state of a member changes, our aggregate state changes.
+        // We trigger both events to replicate the behavior of Backbone.Model.set()
+        this.trigger('change:verified');
+        this.trigger('change');
+    },
+    toggleVerified: function() {
+        if (!this.isPrivate()) {
+            throw new Error('You cannot verify a group conversation. ' +
+                            'You must verify individual contacts.');
+        }
+
+        if (this.isVerified()) {
+            this.save({verified: 'default'});
+        } else {
+            this.save({verified: 'verified'});
+        }
+    },
+
     addKeyChange: function(id) {
         console.log('adding key change advisory for', this.id, this.get('timestamp'));
         var timestamp = Date.now();
@@ -373,12 +453,14 @@
             } else {
                 var promises = [];
                 var members = this.get('members') || [];
+
                 this.contactCollection.reset(
                     members.map(function(number) {
                         var c = ConversationController.create({
                             id   : number,
                             type : 'private'
                         });
+                        this.listenTo(c, 'change:verified', this.onMemberVerifiedChange);
                         promises.push(new Promise(function(resolve) {
                             c.fetch().always(resolve);
                         }));