Pass StringRef by value.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86251 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/MC/MCMachOStreamer.cpp b/lib/MC/MCMachOStreamer.cpp
index 189f072..828b92a 100644
--- a/lib/MC/MCMachOStreamer.cpp
+++ b/lib/MC/MCMachOStreamer.cpp
@@ -134,7 +134,7 @@
   virtual void EmitZerofill(const MCSection *Section, MCSymbol *Symbol = 0,
                             unsigned Size = 0, unsigned ByteAlignment = 0);
 
-  virtual void EmitBytes(const StringRef &Data);
+  virtual void EmitBytes(StringRef Data);
 
   virtual void EmitValue(const MCExpr *Value, unsigned Size);
 
@@ -315,7 +315,7 @@
     SectData.setAlignment(ByteAlignment);
 }
 
-void MCMachOStreamer::EmitBytes(const StringRef &Data) {
+void MCMachOStreamer::EmitBytes(StringRef Data) {
   MCDataFragment *DF = dyn_cast_or_null<MCDataFragment>(getCurrentFragment());
   if (!DF)
     DF = new MCDataFragment(CurSectionData);