[IMP] mail, *: template rendering with abstract thread, adapt thread instantiation, thread `getMessages`/`fetchMessages`, and create mode document thread.

* = im_livechat, im_support

- thread widget now uses abstract thread in `render` method
- thread models have their `init` parameters changed, so that the parent may be optional
- reworked 'creating a new record...' in chatter in create mode:
    > new model CreateModeDocumentThread, which basically is a fake document thread
      with a fake message for its rendering in create mode of the chatter
    > special rendering method of thread_widget for such case: `renderChatterCreateMode`
- renamed thread methods previously named `getMessages` to `fetchMessages`:
    > in order to not conflict with `getMessages`, used for rendering
    > now, `getMessages` always get messages that are locally,
      while `fetchMessages` may fetch messages.

TODO:
    - special thread model for im_livechat (rendering is broken ATM)

1 files changed, 8 insertions, 5 deletions

diff --git a/addons/mail/static/src/js/services/mail_document_thread_manager.js b/addons/mail/static/src/js/services/mail_document_thread_manager.js
index 40301ad724c..b1417d62fc6 100644
--- a/addons/mail/static/src/js/services/mail_document_thread_manager.js
+++ b/addons/mail/static/src/js/services/mail_document_thread_manager.js
@@ -99,11 +99,14 @@ MailManager.include({
     getOrAddDocumentThread: function (params) {
         var thread = this.getDocumentThread(params.resModel, params.resID);
         if (!thread) {
-            thread = new DocumentThread(this, {
-                messageIDs: params.messageIDs,
-                name: params.name,
-                resID: params.resID,
-                resModel: params.resModel,
+            thread = new DocumentThread({
+                parent: this,
+                data: {
+                    messageIDs: params.messageIDs,
+                    name: params.name,
+                    resID: params.resID,
+                    resModel: params.resModel,
+                },
             });
             this._threads.push(thread);
         } else if (params.name) {