Revert rL350048 and rL350050

These patches have broken almost all buildbots on test
DebugInfo/X86/addr_comments.ll. Reverting to green.

llvm-svn: 350052
diff --git a/llvm/lib/CodeGen/AsmPrinter/AddressPool.h b/llvm/lib/CodeGen/AsmPrinter/AddressPool.h
index 44a53b0..2209c7e 100644
--- a/llvm/lib/CodeGen/AsmPrinter/AddressPool.h
+++ b/llvm/lib/CodeGen/AsmPrinter/AddressPool.h
@@ -55,7 +55,7 @@
   void setLabel(MCSymbol *Sym) { AddressTableBaseSym = Sym; }
 
 private:
-  MCSymbol *emitHeader(AsmPrinter &Asm, MCSection *Section);
+  void emitHeader(AsmPrinter &Asm, MCSection *Section);
 
   /// Symbol designates the start of the contribution to the address table.
   MCSymbol *AddressTableBaseSym = nullptr;