Method BackStep

scintilla/src/Partitioning.h:71–76

Move step backward

	// Move step backward
	void BackStep(int partitionDownTo) {
		if (stepLength != 0) {
			body->RangeAddDelta(partitionDownTo+1, stepPartition+1, -stepLength);
		}
		stepPartition = partitionDownTo;
	}

	void Allocate(int growSize) {
		body = new SplitVectorWithRangeAdd(growSize);