NonSFI NaCl: Plumb Exception IRT enough for breakpad.

components/nacl/loader/nacl_helper_linux.cc

Index: components/nacl/loader/nacl_helper_linux.cc
diff --git a/components/nacl/loader/nacl_helper_linux.cc b/components/nacl/loader/nacl_helper_linux.cc
index 15f58eb3a5fba07e50a7b578f240a261be23384e..fe37602546255fa7da6daa1ca2d79ad0ca5dc70e 100644
--- a/components/nacl/loader/nacl_helper_linux.cc
+++ b/components/nacl/loader/nacl_helper_linux.cc
@@ -33,6 +33,7 @@
 #include "components/nacl/common/nacl_switches.h"
 #include "components/nacl/loader/nacl_listener.h"
 #include "components/nacl/loader/nacl_sandbox_linux.h"
+#include "components/nacl/loader/nonsfi/irt_exception_handling.h"
 #include "components/nacl/loader/nonsfi/nonsfi_sandbox.h"
 #include "content/public/common/zygote_fork_delegate_linux.h"
 #include "crypto/nss_util.h"
@@ -123,6 +124,8 @@ void BecomeNaClLoader(const std::vector<int>& child_fds,
   // don't need zygote FD any more
   if (IGNORE_EINTR(close(kNaClZygoteDescriptor)) != 0)
     LOG(ERROR) << "close(kNaClZygoteDescriptor) failed.";
+  if (uses_nonsfi_mode)
+    nacl::nonsfi::InitializeSignalHandler();
   InitializeLayerTwoSandbox(uses_nonsfi_mode);
   base::GlobalDescriptors::GetInstance()->Set(
       kPrimaryIPCChannel,