Remove VISIBILITY_HIDDEN from class/struct found inside anonymous namespaces.
Chris claims we should never have visibility_hidden inside any .cpp file but
that's still not true even after this commit.

llvm-svn: 85042
diff --git a/llvm/lib/Target/ARM/Thumb2SizeReduction.cpp b/llvm/lib/Target/ARM/Thumb2SizeReduction.cpp
index b8879d2..b212c0a 100644
--- a/llvm/lib/Target/ARM/Thumb2SizeReduction.cpp
+++ b/llvm/lib/Target/ARM/Thumb2SizeReduction.cpp
@@ -126,7 +126,7 @@
     { ARM::t2STM,   ARM::tSTM,    ARM::tPUSH,    0,   0,    1,   1,  1,1, 1 },
   };
 
-  class VISIBILITY_HIDDEN Thumb2SizeReduce : public MachineFunctionPass {
+  class Thumb2SizeReduce : public MachineFunctionPass {
   public:
     static char ID;
     Thumb2SizeReduce();