src/vs/editor/contrib/viewportSemanticTokens/viewportSemanticTokens.ts/ViewportSemanticTokensContribution/_removeOutstandingRequest
class ViewportSemanticTokensContribution:	private _removeOutstandingRequest(req: CancelablePromise<SemanticTokens | null | undefined>): void {
		for (let i = 0, len = this._outstandingRequests.length; i < len; i++) {
			if (this._outstandingRequests[i] === req) {
				this._outstandingRequests.splice(i, 1);
				return;
			}
		}
	}