Turn on many more Eclipse warnings, and fix them

- Warn on empty statements, e.g. "for (;;);". These may be
   typos and are easily replaced by "for (;;) {}" which is more
   explicit.
 - Warn on field hiding. This allows cleanup of many acceptance test
   members, at the cost of a couple of renames and the occasional
   suppression (when the field is in a public nested enum that shadows
   a public constant).
 - Warn on unnecessary casts.
 - Warn on unused declared thrown exceptions. In addition to reducing
   method signature length and number of imports, this also eliminated
   some impossible catch blocks.
 - Warn on missing @Override annotations.
 - Warn on unused parameters. This is likely the most controversial,
   as a few relatively common patterns require unused parameters in a
   way that Eclipse can't ignore. However, it also resulted in cleanup
   of a lot of unnecessary injections and method parameters, so I
   think the cost was worth it.

Change-Id: I7224be8b1c798613a127c88507e8cce400679e5d

gerrit-server/src/main/java/com/google/gerrit/server/change/ReviewerJson.java

@@ -29,7 +29,6 @@ import com.google.gerrit.reviewdb.client.PatchSetApproval;
 import com.google.gerrit.reviewdb.server.ReviewDb;
 import com.google.gerrit.server.ApprovalsUtil;
 import com.google.gerrit.server.account.AccountInfo;
-import com.google.gerrit.server.notedb.ChangeNotes;
 import com.google.gerrit.server.project.ChangeControl;
 import com.google.gerrit.server.project.SubmitRuleEvaluator;
 import com.google.gerrit.server.query.change.ChangeData;
@@ -68,8 +67,7 @@ public class ReviewerJson {
     for (ReviewerResource rsrc : rsrcs) {
       ReviewerInfo info = format(new ReviewerInfo(
           rsrc.getUser().getAccountId()),
-          rsrc.getUserControl(),
-          rsrc.getNotes());
+          rsrc.getUserControl());
       loader.put(info);
       infos.add(info);
     }
@@ -81,8 +79,7 @@ public class ReviewerJson {
     return format(ImmutableList.<ReviewerResource> of(rsrc));
   }
 
-  public ReviewerInfo format(ReviewerInfo out, ChangeControl ctl,
-      ChangeNotes changeNotes) throws OrmException {
+  public ReviewerInfo format(ReviewerInfo out, ChangeControl ctl) throws OrmException {
     PatchSet.Id psId = ctl.getChange().currentPatchSetId();
     return format(out, ctl,
         approvalsUtil.byPatchSetUser(db.get(), ctl, psId, out._id));