Add llvm::Metadata to manage metadata used in a context. 
This interface will be used to attach metadata with an instruction.

llvm-svn: 82060
diff --git a/llvm/lib/VMCore/LLVMContext.cpp b/llvm/lib/VMCore/LLVMContext.cpp
index 7d233d9..03f0436 100644
--- a/llvm/lib/VMCore/LLVMContext.cpp
+++ b/llvm/lib/VMCore/LLVMContext.cpp
@@ -70,3 +70,7 @@
   }
   return Changed;
 }
+
+Metadata &LLVMContext::getMetadata() {
+  return pImpl->TheMetadata;
+}