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/Alpha/AlphaBranchSelector.cpp b/llvm/lib/Target/Alpha/AlphaBranchSelector.cpp
index 719ffae..dd94bc9 100644
--- a/llvm/lib/Target/Alpha/AlphaBranchSelector.cpp
+++ b/llvm/lib/Target/Alpha/AlphaBranchSelector.cpp
@@ -21,7 +21,7 @@
 using namespace llvm;
 
 namespace {
-  struct VISIBILITY_HIDDEN AlphaBSel : public MachineFunctionPass {
+  struct AlphaBSel : public MachineFunctionPass {
     static char ID;
     AlphaBSel() : MachineFunctionPass(&ID) {}