Merge qt-r1-dev-plus-aosp-without-vendor (5817612) into stage-aosp-master

Bug: 135460123
Change-Id: I65906d82b14125c0893d5cde0cfebb73bf9e38ab
Merged-In: I1f2564837c33cd4c6c3db6aac3cbaf8c09707da9
diff --git a/core/java/android/net/IpSecManager.java b/core/java/android/net/IpSecManager.java
index 83813da..45d0c73 100644
--- a/core/java/android/net/IpSecManager.java
+++ b/core/java/android/net/IpSecManager.java
@@ -861,6 +861,7 @@
             return mResourceId;
         }
 
+        @NonNull
         @Override
         public String toString() {
             return new StringBuilder()