Check for unstable types in IPC messages.

tools/clang/plugins/Options.h

Index: tools/clang/plugins/Options.h
diff --git a/tools/clang/plugins/Options.h b/tools/clang/plugins/Options.h
index e56084e428d508cb23769e4a1c6865ea3a8657f2..684dab52bbb6047652031108d4565c2b9f3d7fc2 100644
--- a/tools/clang/plugins/Options.h
+++ b/tools/clang/plugins/Options.h
@@ -17,10 +17,10 @@ struct Options {
   // This is needed during the migration from ASTConsumer approach to the
   // RecursiveASTVisitor approach. See https://crbug.com/436357 for details.
   bool check_implicit_copy_ctors = false;
-
   // This is needed for some distributed build-sytems to respect banned
   // paths. See https://crbug.com/583454 for details.
   bool no_realpath = false;
+  bool check_ipc = false;
 };
 
 }  // namespace chrome_checker