Print dex signatures in hidden API warnings

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Test: manual
Bug: 64382372
Change-Id: I232ad63069b736a95aa44c3cf0240c1c2ba2906d
diff --git a/runtime/hidden_api.h b/runtime/hidden_api.h
index 7e41c1d..f476028 100644
--- a/runtime/hidden_api.h
+++ b/runtime/hidden_api.h
@@ -44,12 +44,18 @@
 
 // Issue a warning about field access.
 inline void WarnAboutMemberAccess(ArtField* field) REQUIRES_SHARED(Locks::mutator_lock_) {
-  LOG(WARNING) << "Access to hidden field " << field->PrettyField();
+  std::string tmp;
+  LOG(WARNING) << "Accessing hidden field "
+               << field->GetDeclaringClass()->GetDescriptor(&tmp) << "->"
+               << field->GetName() << ":" << field->GetTypeDescriptor();
 }
 
 // Issue a warning about method access.
 inline void WarnAboutMemberAccess(ArtMethod* method) REQUIRES_SHARED(Locks::mutator_lock_) {
-  LOG(WARNING) << "Access to hidden method " << method->PrettyMethod();
+  std::string tmp;
+  LOG(WARNING) << "Accessing hidden method "
+               << method->GetDeclaringClass()->GetDescriptor(&tmp) << "->"
+               << method->GetName() << method->GetSignature().ToString();
 }
 
 // Returns true if access to `member` should be denied to the caller of the