src/vs/editor/common/tokens/contiguousTokensStore.ts/ContiguousTokensStore/_deleteLines
class ContiguousTokensStore:	private _deleteLines(start: number, deleteCount: number): void {
		if (deleteCount === 0) {
			return;
		}
		if (start + deleteCount > this._len) {
			deleteCount = this._len - start;
		}
		this._lineTokens.splice(start, deleteCount);
		this._len -= deleteCount;
	}