Log error message if CloseNativeLibrary fails

This change adds check for CloseNativeLibrary result and if the
call was unsuccessful logs error message.

Bug: https://issuetracker.google.com/79126103
Test: make
Change-Id: I9280fab7237296c1a06526387aba41f921ffde0f
diff --git a/runtime/jni/java_vm_ext.cc b/runtime/jni/java_vm_ext.cc
index fdf0fee..42406cf 100644
--- a/runtime/jni/java_vm_ext.cc
+++ b/runtime/jni/java_vm_ext.cc
@@ -86,7 +86,10 @@
       self->GetJniEnv()->DeleteWeakGlobalRef(class_loader_);
     }
 
-    android::CloseNativeLibrary(handle_, needs_native_bridge_);
+    std::string error_msg;
+    if (!android::CloseNativeLibrary(handle_, needs_native_bridge_, &error_msg)) {
+      LOG(WARNING) << "Error while unloading native library \"" << path_ << "\": " << error_msg;
+    }
   }
 
   jweak GetClassLoader() const {
diff --git a/runtime/ti/agent.cc b/runtime/ti/agent.cc
index 608f0ee..fc51567 100644
--- a/runtime/ti/agent.cc
+++ b/runtime/ti/agent.cc
@@ -134,7 +134,9 @@
   }
   if (needs_native_bridge) {
     // TODO: Consider support?
-    android::CloseNativeLibrary(dlopen_handle, needs_native_bridge);
+    // The result of this call and error_msg is ignored because the most
+    // relevant error is that native bridge is unsupported.
+    android::CloseNativeLibrary(dlopen_handle, needs_native_bridge, error_msg);
     *error_msg = StringPrintf("Native-bridge agents unsupported: %s", name_.c_str());
     *error = kLoadingError;
     return nullptr;