Revert r51498: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaDecl.cpp?rev=51498&r1=51497&r2=51498&view=diff
Revert r51498: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaDecl.cpp?rev=51498&r1=51497&r2=51498&view=diff

Turns out that there are multiple places where a redefinition diagnostic can be emitted.  A cleaner solution (without touching Sema) is to have
the Driver turn off these diagnostics.  (will submit this patch soon)


git-svn-id: ffe668792ed300d6c2daa1f6eba2e0aa28d7ec6c@51502 91177308-0d34-0410-b5e6-96231b3b80d8

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