Change FATAL message to WARNING message in FindClass

When unable to find the specified class, FindClass was logging a
FATAL message. This terminated the program instead of simply returning
a null pointer as expected. The FATAL message has been replaced with
a WARNING message to fix this behavior.

Bug: 112338190
Test: m -j
Change-Id: I91cc0747a45bff72aa0ffa8f0e1c8fa238469ddf
diff --git a/test/ti-agent/jni_binder.cc b/test/ti-agent/jni_binder.cc
index 32236de..585b4a4 100644
--- a/test/ti-agent/jni_binder.cc
+++ b/test/ti-agent/jni_binder.cc
@@ -223,7 +223,7 @@
   }
 
   // TODO: Implement scanning *all* classloaders.
-  LOG(FATAL) << "Unimplemented";
+  LOG(WARNING) << "Scanning all classloaders unimplemented";
 
   return nullptr;
 }