Fix errorprone warnings that should be errors am: 40710ba037 am: a913564d21 am: d1b4944e6a

Original change: https://android-review.googlesource.com/c/platform/external/caliper/+/2255923

Change-Id: I63ff965b551e1e4939c7ea16b52930f1758dd8ad
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>
diff --git a/Android.bp b/Android.bp
index 6d4619b..b48ee41 100644
--- a/Android.bp
+++ b/Android.bp
@@ -140,6 +140,12 @@
     ],
 
     java_version: "1.8",
+
+    errorprone: {
+        javacflags: [
+            "-Xep:ReturnValueIgnored:WARN",
+        ],
+    },
 }
 
 // Build host dependencies.