src/vs/workbench/contrib/files/common/dirtyFilesIndicator.ts/DirtyFilesIndicator/updateActivityBadge
class DirtyFilesIndicator:	private updateActivityBadge(): void {
		const dirtyCount = this.lastKnownDirtyCount = this.workingCopyService.dirtyCount;

		// Indicate dirty count in badge if any
		if (dirtyCount > 0) {
			this.badgeHandle.value = this.activityService.showViewContainerActivity(
				VIEWLET_ID,
				{
					badge: new NumberBadge(dirtyCount, num => num === 1 ? nls.localize('dirtyFile', "1 unsaved file") : nls.localize('dirtyFiles', "{0} unsaved files", dirtyCount)),
					clazz: 'explorer-viewlet-label'
				}
			);
		} else {
			this.badgeHandle.clear();
		}
	}