[Reassociate] Use test cases that can actually be optimized to verify optional flags are cleared.  The reassociation pass was just reordering the leaf nodes in the previous test cases.
[Reassociate] Use test cases that can actually be optimized to verify optional
flags are cleared.  The reassociation pass was just reordering the leaf nodes
in the previous test cases.

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@222250 91177308-0d34-0410-b5e6-96231b3b80d8

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