Work in the direction of hard float quick ABIs.

Pass a shorty to ArtMethod::Invoke so that register setup can use it.
Document x86-64 ABI.
Add extra debug output for one JNI native method registration fails, namely a
dump of the Class and its dex file's location.
Add hack to get testing of OatMethod's without GC maps working in 64bit.

Change-Id: Ic06b68e18eac33637df2caf5e7e775ff95ae70f3
diff --git a/runtime/debugger.cc b/runtime/debugger.cc
index 8280c7c..53ac5cc 100644
--- a/runtime/debugger.cc
+++ b/runtime/debugger.cc
@@ -3019,7 +3019,7 @@
   MethodHelper mh(m.get());
   ArgArray arg_array(mh.GetShorty(), mh.GetShortyLength());
   arg_array.BuildArgArray(soa, pReq->receiver, reinterpret_cast<jvalue*>(pReq->arg_values));
-  InvokeWithArgArray(soa, m.get(), &arg_array, &pReq->result_value, mh.GetShorty()[0]);
+  InvokeWithArgArray(soa, m.get(), &arg_array, &pReq->result_value, mh.GetShorty());
 
   mirror::Throwable* exception = soa.Self()->GetException(NULL);
   soa.Self()->ClearException();