log opening timeline

also load the timeline when opening it in the room, so logging
starts in the room (and we don't need to pass the logger to Timeline)
and also API-wise it makes more sense to
not return uninitialized objects

src/domain/session/room/RoomViewModel.js

@@ -41,12 +41,12 @@ export class RoomViewModel extends ViewModel {
     async load() {
         this._room.on("change", this._onRoomChange);
         try {
+            const timeline = await this._room.openTimeline();
             const timelineVM = this.track(new TimelineViewModel(this.childOptions({
                 room: this._room,
-                timeline: this._room.openTimeline(),
+                timeline,
                 ownUserId: this._ownUserId,
             })));
-            await timelineVM.load();
             this._timelineVM = timelineVM;
             this.emitChange("timelineViewModel");
         } catch (err) {

src/domain/session/room/timeline/TimelineViewModel.js

@@ -40,16 +40,9 @@ export class TimelineViewModel extends ViewModel {
         super(options);
         const {room, timeline, ownUserId} = options;
         this._timeline = this.track(timeline);
-        // once we support sending messages we could do
-        // timeline.entries.concat(timeline.pendingEvents)
-        // for an ObservableList that also contains local echos
         this._tiles = new TilesCollection(timeline.entries, tilesCreator(this.childOptions({room, ownUserId})));
     }
 
-    async load() {
-        await this._timeline.load();
-    }
-
     /**
      * @return {bool} startReached if the start of the timeline was reached
      */

src/matrix/room/Room.js

@@ -575,7 +575,9 @@ export class Room extends EventEmitter {
     }
 
     /** @public */
-    openTimeline() {
+    openTimeline(log = null) {
+        return this._platform.logger.wrapOrRun(log, "open timeline", async log => {
+            log.set("id", this.id);
             if (this._timeline) {
                 throw new Error("not dealing with load race here for now");
             }
@@ -586,19 +588,21 @@ export class Room extends EventEmitter {
                 fragmentIdComparer: this._fragmentIdComparer,
                 pendingEvents: this._sendQueue.pendingEvents,
                 closeCallback: () => {
-                console.log(`closing the timeline for ${this._roomId}`);
                     this._timeline = null;
                     if (this._roomEncryption) {
                         this._roomEncryption.notifyTimelineClosed();
                     }
                 },
                 user: this._user,
-            clock: this._platform.clock
+                clock: this._platform.clock,
+                logger: this._platform.logger,
             });
             if (this._roomEncryption) {
                 this._timeline.enableEncryption(this._decryptEntries.bind(this, DecryptionSource.Timeline));
             }
+            await this._timeline.load();
             return this._timeline;
+        });
     }
 
     get mediaRepository() {