Revert alignment assumptions changes
Revert alignment assumptions changes

Revert r351104-6, r351109, r351110, r351119, r351134, and r351153. These
changes fail on the sanitizer bots.

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@351159 91177308-0d34-0410-b5e6-96231b3b80d8

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