Stop messing with the 'g' group of options in CompilerInvocation.

With this change, most 'g' options are rejected by CompilerInvocation.
They remain only as Driver options. The new way to request debug info
from cc1 is with "-debug-info-kind={line-tables-only|limited|standalone}"
and "-dwarf-version={2|3|4}". In the absence of a command-line option
to specify Dwarf version, the Toolchain decides it, rather than placing
Toolchain-specific logic in CompilerInvocation.

Also fix a bug in the Windows compatibility argument parsing
in which the "rightmost argument wins" principle failed.

Differential Revision: http://reviews.llvm.org/D13221

llvm-svn: 249655
diff --git a/clang/test/CodeGenCXX/linetable-fnbegin.cpp b/clang/test/CodeGenCXX/linetable-fnbegin.cpp
index c65dfb8..f4cf53b 100644
--- a/clang/test/CodeGenCXX/linetable-fnbegin.cpp
+++ b/clang/test/CodeGenCXX/linetable-fnbegin.cpp
@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -emit-llvm -g %s -o - | FileCheck %s
+// RUN: %clang_cc1 -emit-llvm -debug-info-kind=limited %s -o - | FileCheck %s
 // Test that the line table info for Foo<T>::bar() is pointing to the
 // right header file.
 // CHECK: define{{.*}}bar