Cleanups and fixes for sigchain_test.cc

Add a missing call to RaiseHandled.

Test: sigchain_test
Change-Id: I1a7fde742fa31b30201df228970ae62052dbcf12
diff --git a/sigchainlib/sigchain_test.cc b/sigchainlib/sigchain_test.cc
index 4ef98c2..dfa3b37 100644
--- a/sigchainlib/sigchain_test.cc
+++ b/sigchainlib/sigchain_test.cc
@@ -231,8 +231,8 @@
 
   // ...and after.
   art::EnsureFrontOfChain(SIGSEGV);
+  RaiseHandled();
   ASSERT_EQ(0, called);
-  called = 0;
 
   RaiseUnhandled();
   ASSERT_EQ(1, called);