src/vs/workbench/services/workingCopy/common/workingCopyService.ts/WorkingCopyService/dirtyCount
class WorkingCopyService:	get dirtyCount(): number {
		let totalDirtyCount = 0;

		for (const workingCopy of this._workingCopies) {
			if (workingCopy.isDirty()) {
				totalDirtyCount++;
			}
		}

		return totalDirtyCount;
	}