Add a couple missing @Nullable annotations in java.security.

Author: cpovirk

src/java.base/share/classes/java/security/KeyStore.java

@@ -1430,7 +1430,7 @@ public final boolean isCertificateEntry(String alias)
      * @throws    CertificateException if any of the certificates included in
      * the keystore data could not be stored
      */
-    public final void store(OutputStream stream, char[] password)
+    public final void store(OutputStream stream, char @Nullable [] password)
         throws KeyStoreException, IOException, NoSuchAlgorithmException,
             CertificateException
     {

src/java.base/share/classes/java/security/ProtectionDomain.java

@@ -133,7 +133,7 @@ public ProtectionDomain(@Nullable CodeSource codesource,
     public ProtectionDomain(@Nullable CodeSource codesource,
                             @Nullable PermissionCollection permissions,
                             @Nullable ClassLoader classloader,
-                            Principal[] principals) {
+                            Principal @Nullable [] principals) {
         this.codesource = codesource;
         if (permissions != null) {
             this.permissions = permissions;