src/vs/workbench/contrib/tasks/common/problemCollectors.ts/AbstractProblemCollector/tryFindMarker
class AbstractProblemCollector:	protected tryFindMarker(line: string): ProblemMatch | null {
		let result: ProblemMatch | null = null;
		if (this.activeMatcher) {
			result = this.activeMatcher.next(line);
			if (result) {
				this.captureMatch(result);
				return result;
			}
			this.clearBuffer();
			this.activeMatcher = null;
		}
		if (this.buffer.length < this.bufferLength) {
			this.buffer.push(line);
		} else {
			let end = this.buffer.length - 1;
			for (let i = 0; i < end; i++) {
				this.buffer[i] = this.buffer[i + 1];
			}
			this.buffer[end] = line;
		}

		result = this.tryMatchers();
		if (result) {
			this.clearBuffer();
		}
		return result;
	}