[SEH] Fix wrong argument passes to the call of OutlinedFinally.

When return out of __try block.  In this test case, currently "false" is
passed to OutlinedFinally's call.  "true" should be passed to indicate
abnormal terminations.

The rule: Except _leave and fall-through at the end, all other exits
in a _try (return/goto/continue/break) are considered as abnormal
terminations, NormalCleanupDestSlot is used to indicate abnormal
terminations.

The problem is, during the processing abnormal terminations,
the ExitSwitch is used.  However, in this case, Existswitch is route out.

One way to fix is to skip route it without a switch. So proper
abnormal termination's code could be generated.

Differential Revision: https://reviews.llvm.org/D158233