Adapt to Account being an AutoValue

Change-Id: Iacf5464614c7ea036abfec8b9ad6d6fca4ef103d

src/main/java/com/googlesource/gerrit/plugins/avatars/gravatar/GravatarAvatarProvider.java

diff --git a/src/main/java/com/googlesource/gerrit/plugins/avatars/gravatar/GravatarAvatarProvider.java b/src/main/java/com/googlesource/gerrit/plugins/avatars/gravatar/GravatarAvatarProvider.java
index cc6d69f..f4aedcc 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/avatars/gravatar/GravatarAvatarProvider.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/avatars/gravatar/GravatarAvatarProvider.java
@@ -65,11 +65,11 @@
 
   @Override
   public String getUrl(IdentifiedUser forUser, int imageSize) {
-    if (forUser.getAccount().getPreferredEmail() == null) {
+    if (forUser.getAccount().preferredEmail() == null) {
       return null;
     }
     final String email =
-        forUser.getAccount().getPreferredEmail().trim().toLowerCase();
+        forUser.getAccount().preferredEmail().trim().toLowerCase();
     final byte[] emailMd5;
     try {
       MessageDigest digest = MessageDigest.getInstance("MD5");