Revert "Fix WifiHandler for MSim"

This reverts commit 5e194a9036e71a387b118ce660a4b6bbab2b38f1.
Fix WifiHandler for MSim

Commit 7c26a5cce74332bc48da9e894a835f2fe795431c attempted to fix
this issue by adding back the old code, but it needs to be a method
that can be called by MSimNetworkController. So sync it back to caf
to fix the merge issue.

Change-Id: Ifc721cbf372ec50810924d7ac6d55f54663458a1