_getOverwrittenModuleSourceTypes(module) {
		let newSet = false;
		let sourceTypes;
		for (const chunk of this.getModuleChunksIterable(module)) {
			const cgc = this._getChunkGraphChunk(chunk);
			if (cgc.sourceTypesByModule === undefined) return;
			const st = cgc.sourceTypesByModule.get(module);
			if (st === undefined) return;
			if (!sourceTypes) {
				sourceTypes = st;
			} else if (!newSet) {
				for (const type of st) {
					if (!newSet) {
						if (!sourceTypes.has(type)) {
							newSet = true;
							sourceTypes = new Set(sourceTypes);
							sourceTypes.add(type);
						}
					} else {
						sourceTypes.add(type);
					}
				}
			} else {
				for (const type of st) sourceTypes.add(type);
			}
		}

		return sourceTypes;
	}
@param {Module} module module
@returns {Set<string> | undefined} source types