Check for null before dereference

Previously we would throw an NPE when calling contains() on a null
string. Move the explicit check before this to give a better error
message (but still throw NPE).

Bug: 328268682
Test: atest MicrodroidTests
Change-Id: I3fb3926dd5020893a6356272f6e50d21cc99036d
diff --git a/java/framework/src/android/system/virtualmachine/VirtualMachineConfig.java b/java/framework/src/android/system/virtualmachine/VirtualMachineConfig.java
index 693a7d7..12aeac8 100644
--- a/java/framework/src/android/system/virtualmachine/VirtualMachineConfig.java
+++ b/java/framework/src/android/system/virtualmachine/VirtualMachineConfig.java
@@ -829,12 +829,12 @@
         @SystemApi
         @NonNull
         public Builder setPayloadBinaryName(@NonNull String payloadBinaryName) {
+            requireNonNull(payloadBinaryName, "payloadBinaryName must not be null");
             if (payloadBinaryName.contains(File.separator)) {
                 throw new IllegalArgumentException(
                         "Invalid binary file name: " + payloadBinaryName);
             }
-            mPayloadBinaryName =
-                    requireNonNull(payloadBinaryName, "payloadBinaryName must not be null");
+            mPayloadBinaryName = payloadBinaryName;
             return this;
         }