src/vs/editor/contrib/folding/browser/foldingModel.ts/FoldingModel/removeManualRanges
class FoldingModel:	public removeManualRanges(ranges: ILineRange[]) {
		const newFoldingRanges: FoldRange[] = new Array();
		const intersects = (foldRange: FoldRange) => {
			for (const range of ranges) {
				if (!(range.startLineNumber > foldRange.endLineNumber || foldRange.startLineNumber > range.endLineNumber)) {
					return true;
				}
			}
			return false;
		};
		for (let i = 0; i < this._regions.length; i++) {
			const foldRange = this._regions.toFoldRange(i);
			if (foldRange.source === FoldSource.provider || !intersects(foldRange)) {
				newFoldingRanges.push(foldRange);
			}
		}
		this.updatePost(FoldingRegions.fromFoldRanges(newFoldingRanges));
	}