[LCG] Special case the removal of self edges. These don't impact the SCC graph in any way because we don't track edges in the SCC graph, just nodes. This also lets us add a nice assert about the invariant that we're working on at least a certain number of nodes within the SCC.
[LCG] Special case the removal of self edges. These don't impact the SCC
graph in any way because we don't track edges in the SCC graph, just
nodes. This also lets us add a nice assert about the invariant that
we're working on at least a certain number of nodes within the SCC.

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@207305 91177308-0d34-0410-b5e6-96231b3b80d8

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