trivial micro-optimization: lazily call the virtual method instead of eagerly calling it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172953 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Bitcode/Reader/BitcodeReader.cpp

@@ -796,7 +796,7 @@ bool BitcodeReader::ParseMetadata() {
     default:  // Default behavior: ignore.
       break;
     case bitc::METADATA_NAME: {
-      // Read named of the named metadata.
+      // Read name of the named metadata.
       SmallString<8> Name(Record.begin(), Record.end());
       Record.clear();
       Code = Stream.ReadCode();