Bug 955048 - Tags are never really removed from contacts, r=clokep.

chat/components/src/imContacts.js

@@ -434,12 +434,7 @@ Contact.prototype = {
     if (!this.hasTag(aTag) || this._isTagInherited(aTag))
       return;
 
-    let statement = DBConn.createStatement("DELETE FROM contact_tag " +
-                                           "WHERE contact_id = :contactId " +
-                                           "AND tag_id = :tagId");
-    statement.params.contactId = this.id;
-    statement.params.tagId = aTag.id;
-    statement.executeAsync();
+    this._removeContactTagRow(aTag);
 
     this._tags = this._tags.filter(function(tag) tag.id != aTag.id);
     aTag = TagsById[aTag.id];
@@ -450,6 +445,14 @@ Contact.prototype = {
       observer.observe(aTag, "contact-moved-out", null);
     Services.obs.notifyObservers(this, "contact-tag-removed", aTag.id);
   },
+  _removeContactTagRow: function(aTag) {
+    let statement = DBConn.createStatement("DELETE FROM contact_tag " +
+                                           "WHERE contact_id = :contactId " +
+                                           "AND tag_id = :tagId");
+    statement.params.contactId = this.id;
+    statement.params.tagId = aTag.id;
+    statement.executeAsync();
+  },
   hasTag: function(aTag) this._tags.some(function (t) t.id == aTag.id),
   _massMove: false,
   removeTag: function(aTag) {
@@ -1346,8 +1349,14 @@ ContactsService.prototype = {
     statement.params.newTagId = aNewTag.id;
     statement.execute();
 
+    let contact = ContactsById[buddy.contact.id];
+
+    // aNewTag is now inherited by the contact from an account buddy, so avoid
+    // keeping direct tag <-> contact links in the contact_tag table.
+    contact._removeContactTagRow(aNewTag);
+
     buddy.observe(aAccountBuddy, "account-buddy-moved");
-    ContactsById[buddy.contact.id]._moved(aOldTag, aNewTag);
+    contact._moved(aOldTag, aNewTag);
   },
 
   storeAccount: function(aId, aUserName, aPrplId) {

im/content/contact.xml

@@ -158,8 +158,13 @@
              aTopic == "contact-status-changed")
            this.update();
          else if (aTopic == "contact-signed-on") {
-           if (this.state == "fading")
-             this.state = "visible";
+           if (this.state == "fading") {
+             // If the contact is fading out because it's no longer in this group,
+             // ignore the signed-on notification; otherwise cancel the animation.
+             let groupId = this.group.tag.id;
+             if (this.contact.getTags().some(function(t) t.id == groupId))
+               this.state = "visible";
+           }
          }
          else if (aTopic == "contact-removed" ||
                   (aTopic == "contact-moved-out" && aSubject.id == this.group.tag.id) ||