Add debug code for saving dex file inputs

Also improve some other logging.

Bug: 13078746
Change-Id: Ic7a7c201b935e2b117ddc38b652cf39152fe42dc
diff --git a/runtime/dex_file.cc b/runtime/dex_file.cc
index 5e2b9ff..a3415d3 100644
--- a/runtime/dex_file.cc
+++ b/runtime/dex_file.cc
@@ -721,7 +721,8 @@
   }
 
   if (it.HasNext()) {
-    LOG(ERROR) << "invalid stream - problem with parameter iterator in " << GetLocation();
+    LOG(ERROR) << "invalid stream - problem with parameter iterator in " << GetLocation()
+               << " for method " << PrettyMethod(method_idx, *this);
     return;
   }