Oilpan: Add static_cast to adjustAndMark implementation to assert that USING_GARBAGE_COLLECTED_MIXIN is given a correct type.
Oilpan: Add static_cast to adjustAndMark implementation to assert that USING_GARBAGE_COLLECTED_MIXIN is given a correct type.

R=haraken@chromium.org
BUG=

Review URL: https://codereview.chromium.org/298833002

git-svn-id: bf5cd6ccde378db821296732a091cfbcf5285fbd@174565 bbb929c8-8fbe-4397-9dbb-9b2b20218538

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