Revert "Tidy gAborting."

Creates infinite loop: b/18674776.

This reverts commit 015b137efb434528173779bc3ec8d72494456254.

Change-Id: I67fe310d2e95ee2ec37bec842be06fb1123b6f4e
diff --git a/runtime/runtime_linux.cc b/runtime/runtime_linux.cc
index 9273091..1de035c 100644
--- a/runtime/runtime_linux.cc
+++ b/runtime/runtime_linux.cc
@@ -284,6 +284,7 @@
   }
   handlingUnexpectedSignal = true;
 
+  gAborting++;  // set before taking any locks
   MutexLock mu(Thread::Current(), *Locks::unexpected_signal_lock_);
 
   bool has_address = (signal_number == SIGILL || signal_number == SIGBUS ||