Remove the -cxx-abi command-line flag.

This makes the C++ ABI depend entirely on the target: MS ABI for -win32 triples,
Itanium otherwise. It's no longer possible to do weird combinations.

To be able to run a test with a specific ABI without constraining it to a
specific triple, new substitutions are added to lit: %itanium_abi_triple and
%ms_abi_triple can be used to get the current target triple adjusted to the
desired ABI. For example, if the test suite is running with the i686-pc-win32
target, %itanium_abi_triple will expand to i686-pc-mingw32.

Differential Revision: http://llvm-reviews.chandlerc.com/D2545

llvm-svn: 199250
diff --git a/clang/test/CodeGenCXX/2004-03-09-UnmangledBuiltinMethods.cpp b/clang/test/CodeGenCXX/2004-03-09-UnmangledBuiltinMethods.cpp
index 0f82091..03c4ed6 100644
--- a/clang/test/CodeGenCXX/2004-03-09-UnmangledBuiltinMethods.cpp
+++ b/clang/test/CodeGenCXX/2004-03-09-UnmangledBuiltinMethods.cpp
@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -emit-llvm -cxx-abi itanium -o - %s | FileCheck %s
+// RUN: %clang_cc1 -emit-llvm -triple %itanium_abi_triple -o - %s | FileCheck %s
 
 // CHECK: _ZN11AccessFlags6strlenEv
 struct AccessFlags {