src/vs/workbench/contrib/output/common/outputChannelModel.ts/AbstractFileOutputChannelModel/clear
class AbstractFileOutputChannelModel:	clear(till?: number): void {
		if (this.modelUpdater.isScheduled()) {
			this.modelUpdater.cancel();
			this.onUpdateModelCancelled();
		}
		if (this.model) {
			this.model.setValue('');
		}
		this.endOffset = isNumber(till) ? till : this.endOffset;
		this.startOffset = this.endOffset;
	}