Remove manual support of JS scheduling events

We kept them for a couple of milestones for backwards compat. These are
now computed automatically based on flow events that we dispatch as of
recently [1].

[1] https://chromium-review.googlesource.com/c/v8/v8/+/6021036

Fixed: 383974422
Change-Id: I77a65080838d043c7cfa64ad47f4a924d455fdb9
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/6237086
Auto-Submit: Andres Olivares <[email protected]>
Reviewed-by: Jack Franklin <[email protected]>
Commit-Queue: Jack Franklin <[email protected]>

Author: and-oli

front_end/models/trace/handlers/InitiatorsHandler.ts

@@ -30,26 +30,15 @@ const eventToInitiatorMap = new Map<Types.Events.Event, Types.Events.Event>();
 // multiple events, hence why the value for this map is an array.
 const initiatorToEventsMap = new Map<Types.Events.Event, Types.Events.Event[]>();
 
-// Note: we are keeping the parsing of the following async JS schedulers
-// for backwards compatibility only. They are targeted to be removed
-// completely by M134. See more details at crbug.com/383974422
-// TODO(andoli): remove manual parsing of async JS schedulers.
-const requestAnimationFrameEventsById: Map<number, Types.Events.RequestAnimationFrame> = new Map();
-const timerInstallEventsById: Map<number, Types.Events.TimerInstall> = new Map();
-const requestIdleCallbackEventsById: Map<number, Types.Events.RequestIdleCallback> = new Map();
-
 const webSocketCreateEventsById: Map<number, Types.Events.WebSocketCreate> = new Map();
 const schedulePostTaskCallbackEventsById: Map<number, Types.Events.SchedulePostTaskCallback> = new Map();
 
 export function reset(): void {
   lastScheduleStyleRecalcByFrame.clear();
   lastInvalidationEventForFrame.clear();
   lastUpdateLayoutTreeByFrame.clear();
-  timerInstallEventsById.clear();
   eventToInitiatorMap.clear();
   initiatorToEventsMap.clear();
-  requestAnimationFrameEventsById.clear();
-  requestIdleCallbackEventsById.clear();
   webSocketCreateEventsById.clear();
   schedulePostTaskCallbackEventsById.clear();
 }
@@ -128,36 +117,6 @@ export function handleEvent(event: Types.Events.Event): void {
     }
     // Now clear the last invalidation for the frame: the last invalidation has been linked to a Layout event, so it cannot be the initiator for any future layouts.
     lastInvalidationEventForFrame.delete(event.args.beginData.frame);
-  } else if (Types.Events.isRequestAnimationFrame(event)) {
-    requestAnimationFrameEventsById.set(event.args.data.id, event);
-  } else if (Types.Events.isFireAnimationFrame(event)) {
-    // If we get a fire event, that means we should have had the
-    // RequestAnimationFrame event by now. If so, we can set that as the
-    // initiator for the fire event.
-    const matchingRequestEvent = requestAnimationFrameEventsById.get(event.args.data.id);
-    if (matchingRequestEvent) {
-      storeInitiator({
-        event,
-        initiator: matchingRequestEvent,
-      });
-    }
-  } else if (Types.Events.isTimerInstall(event)) {
-    timerInstallEventsById.set(event.args.data.timerId, event);
-  } else if (Types.Events.isTimerFire(event)) {
-    const matchingInstall = timerInstallEventsById.get(event.args.data.timerId);
-    if (matchingInstall) {
-      storeInitiator({event, initiator: matchingInstall});
-    }
-  } else if (Types.Events.isRequestIdleCallback(event)) {
-    requestIdleCallbackEventsById.set(event.args.data.id, event);
-  } else if (Types.Events.isFireIdleCallback(event)) {
-    const matchingRequestEvent = requestIdleCallbackEventsById.get(event.args.data.id);
-    if (matchingRequestEvent) {
-      storeInitiator({
-        event,
-        initiator: matchingRequestEvent,
-      });
-    }
   } else if (Types.Events.isWebSocketCreate(event)) {
     webSocketCreateEventsById.set(event.args.data.identifier, event);
   } else if (Types.Events.isWebSocketInfo(event) || Types.Events.isWebSocketTransfer(event)) {