Fix Checkstyle warnings related to class and member modifier order

Change the order of class and member modifiers to follow the order
defined in the Java Language Specification and the Google Java
Style guide [1].

[1] https://google-styleguide.googlecode.com/svn/trunk/javaguide.html#s4.8.7-modifiers

Change-Id: Ic7f85cb4d15f49159095aa37d3c41dbffd69c805

gerrit-server/src/main/java/com/google/gerrit/server/plugins/PluginGuiceEnvironment.java

@@ -518,10 +518,12 @@ public class PluginGuiceEnvironment {
     bindings.remove(Key.get(Injector.class));
     bindings.remove(Key.get(java.util.logging.Logger.class));
 
-    final @Nullable Binding<HttpServletRequest> requestBinding =
+    @Nullable
+    final Binding<HttpServletRequest> requestBinding =
         src.getExistingBinding(Key.get(HttpServletRequest.class));
 
-    final @Nullable Binding<HttpServletResponse> responseBinding =
+    @Nullable
+    final Binding<HttpServletResponse> responseBinding =
         src.getExistingBinding(Key.get(HttpServletResponse.class));
 
     return new AbstractModule() {