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/Layout/ms-x86-empty-base-after-base-with-vbptr.cpp b/clang/test/Layout/ms-x86-empty-base-after-base-with-vbptr.cpp
index 8d71b05..224594e 100644
--- a/clang/test/Layout/ms-x86-empty-base-after-base-with-vbptr.cpp
+++ b/clang/test/Layout/ms-x86-empty-base-after-base-with-vbptr.cpp
@@ -1,6 +1,6 @@
-// RUN: %clang_cc1 -fno-rtti -emit-llvm-only -triple i686-pc-win32 -fdump-record-layouts -cxx-abi microsoft %s 2>/dev/null \
+// RUN: %clang_cc1 -fno-rtti -emit-llvm-only -triple i686-pc-win32 -fdump-record-layouts %s 2>/dev/null \
 // RUN:            | FileCheck %s
-// RUN: %clang_cc1 -fno-rtti -emit-llvm-only -triple x86_64-pc-win32 -fdump-record-layouts -cxx-abi microsoft %s 2>/dev/null \
+// RUN: %clang_cc1 -fno-rtti -emit-llvm-only -triple x86_64-pc-win32 -fdump-record-layouts %s 2>/dev/null \
 // RUN:            | FileCheck %s -check-prefix CHECK-X64