The core change here is to the loop in
`SimpleRegionNormalizer#computeMergeNormalizationPlans`. It's a nested
loop that walks the table's region chain once, looking for contiguous
sequences of regions that meet the criteria for merge. The outer loop
tracks the starting point of the next sequence, the inner loop looks
for the end of that sequence. A single sequence becomes an instance of
`MergeNormalizationPlan`.
Signed-off-by: Huaxiang Sun <huaxiangsun@apache.org>
b84e2f598b