fix(core): avoid deleting idle bucket created during another bucket's… - #70959

When a bucket was emptied and removed during its own drain, and a new bucket with the same key was created in the same drain, the end of the drain deleted the new bucket from the map instead of its own. The new bucket's idle request could then no longer be cancelled on removal or on destroy, and could run after the injector was destroyed (NG0205).

Only delete the bucket from the map if it is still the one stored under that key.

Fixes #70941

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PR Type

What kind of change does this PR introduce?

• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• CI related changes
• Documentation content changes
• angular.dev application / infrastructure changes
• Other... Please describe:

What is the current behavior?

While an idle bucket is draining, a trigger cleanup can empty it, and remove() then deletes it from buckets. If ApplicationRef._tick() in the same drain creates a new @defer (on idle) block, add() creates a new bucket under the same key and requests a new idle callback.

When the drain finishes, the old bucket's queue is empty, so scheduleBucket() calls this.buckets.delete(key). This removes the new bucket from the map, not the old one. After that:

• remove() can't find the bucket, so destroying the view doesn't cancel the request.
• ngOnDestroy() only cancels buckets that are still in the map, so destroying the injector doesn't cancel it either.

When the orphaned callback runs later, it can throw NG0205: Injector has already been destroyed, or load dependencies for a destroyed defer block.

Issue Number: #70941

What is the new behavior?

At the end of a drain, the bucket is removed from the map only if the map still holds that same bucket (this.buckets.get(key) === bucket). A bucket created during the drain stays in the map, so its idle request is cancelled correctly when its callback is removed or when the scheduler is destroyed.

Does this PR introduce a breaking change?

• Yes
• No

Other information