Use existing LiveInterval methods to simplify live interval merging.  Thanks to Evan for pointing these out.
Use existing LiveInterval methods to simplify live interval merging.  Thanks to Evan for pointing these out.


git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@54225 91177308-0d34-0410-b5e6-96231b3b80d8

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