Driver: Introduce OptSpecifier class for protecting access to an option id.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@89310 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Driver/ToolChains.cpp b/lib/Driver/ToolChains.cpp
index 8242d31..a9a2d0f 100644
--- a/lib/Driver/ToolChains.cpp
+++ b/lib/Driver/ToolChains.cpp
@@ -366,7 +366,7 @@
     // Sob. These is strictly gcc compatible for the time being. Apple
     // gcc translates options twice, which means that self-expanding
     // options add duplicates.
-    switch ((options::ID) A->getOption().getId()) {
+    switch ((options::ID) A->getOption().getID()) {
     default:
       DAL->append(A);
       break;