mcstreamerize .file and .file. This also fixes an issue where the

normal form of .file would fail if the filename had a weird character
in it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94437 91177308-0d34-0410-b5e6-96231b3b80d8

lib/MC/MCNullStreamer.cpp

@@ -58,6 +58,8 @@ namespace {
     virtual void EmitValueToOffset(const MCExpr *Offset,
                                    unsigned char Value = 0) {}
     
+    virtual void EmitFileDirective(StringRef Filename) {}
+    virtual void EmitDwarfFileDirective(unsigned FileNo,StringRef Filename) {}
     virtual void EmitInstruction(const MCInst &Inst) {}
 
     virtual void Finish() {}