Fix Granite style class deprecations

src/Dialogs/AvatarDialog.vala

@@ -36,16 +36,16 @@ public class SwitchboardPlugUserAccounts.Dialogs.AvatarDialog : Granite.MessageD
 
     construct {
         var button_change = add_button (_("Change Avatar"), Gtk.ResponseType.OK);
-        button_change.add_css_class (Granite.STYLE_CLASS_SUGGESTED_ACTION);
+        button_change.add_css_class (Granite.CssClass.SUGGESTED);
 
         response.connect (on_response);
 
         try {
             var pixbuf = new Gdk.Pixbuf.from_file (pixbuf_path).apply_embedded_orientation ();
 
             cropview = new Widgets.CropView (pixbuf, 400);
-            cropview.add_css_class (Granite.STYLE_CLASS_CARD);
-            cropview.add_css_class (Granite.STYLE_CLASS_CHECKERBOARD);
+            cropview.add_css_class (Granite.CssClass.CARD);
+            cropview.add_css_class (Granite.CssClass.CHECKERBOARD);
 
             custom_bin.append (cropview);
         } catch (Error e) {

src/Dialogs/ChangePasswordDialog.vala

@@ -39,7 +39,7 @@ public class SwitchboardPlugUserAccounts.ChangePasswordDialog : Granite.Dialog {
             };
 
             current_pw_error = new ErrorRevealer (_("Authentication failed"));
-            current_pw_error.label_widget.add_css_class (Granite.STYLE_CLASS_ERROR);
+            current_pw_error.label_widget.add_css_class (Granite.CssClass.ERROR);
 
             form_box.append (current_pw_label);
             form_box.append (current_pw_entry);
@@ -75,7 +75,7 @@ public class SwitchboardPlugUserAccounts.ChangePasswordDialog : Granite.Dialog {
 
         var button_change = add_button (_("Change Password"), Gtk.ResponseType.OK);
         button_change.sensitive = false;
-        button_change.add_css_class (Granite.STYLE_CLASS_SUGGESTED_ACTION);
+        button_change.add_css_class (Granite.CssClass.SUGGESTED);
 
         pw_editor.validation_changed.connect (() => {
             var permission = get_permission ();

src/Dialogs/FingerprintDialog.vala

@@ -80,7 +80,7 @@ public class SwitchboardPlugUserAccounts.FingerprintDialog : Granite.Dialog {
         try {
             fp_utils = new SwitchboardPlugUserAccounts.FPUtils ();
             finish_button = add_button (_("Finish"), Gtk.ResponseType.OK);
-            finish_button.add_css_class (Granite.STYLE_CLASS_SUGGESTED_ACTION);
+            finish_button.add_css_class (Granite.CssClass.SUGGESTED);
             finish_button.sensitive = false;
             set_default_widget (finish_button);
         } catch (Error e) {

src/Dialogs/NewUserDialog.vala

@@ -39,7 +39,7 @@ public class SwitchboardPlugUserAccounts.NewUserDialog : Granite.Dialog {
         };
 
         username_error_revealer = new ErrorRevealer (".");
-        username_error_revealer.label_widget.add_css_class (Granite.STYLE_CLASS_ERROR);
+        username_error_revealer.label_widget.add_css_class (Granite.CssClass.ERROR);
 
         pw_editor = new Widgets.PasswordEditor ();
 
@@ -72,7 +72,7 @@ public class SwitchboardPlugUserAccounts.NewUserDialog : Granite.Dialog {
         create_button = (Gtk.Button) add_button (_("Create User"), Gtk.ResponseType.OK);
         create_button.receives_default = true;
         create_button.sensitive = false;
-        create_button.add_css_class (Granite.STYLE_CLASS_SUGGESTED_ACTION);
+        create_button.add_css_class (Granite.CssClass.SUGGESTED);
 
         realname_entry.changed.connect (() => {
             var username = gen_username (realname_entry.text);

src/Views/UserSettingsView.vala

@@ -112,7 +112,7 @@ namespace SwitchboardPlugUserAccounts.Widgets {
                 margin_start = 6,
                 tooltip_text = NO_PERMISSION_STRING
             };
-            full_name_lock.add_css_class (Granite.STYLE_CLASS_DIM_LABEL);
+            full_name_lock.add_css_class (Granite.CssClass.DIM);
 
             lock_switch = new Gtk.Switch () {
                 action_name = "user.enable",
@@ -325,7 +325,7 @@ namespace SwitchboardPlugUserAccounts.Widgets {
             var remove_user_button = new Gtk.Button.with_label (_("Remove Account")) {
                 sensitive = false
             };
-            remove_user_button.add_css_class (Granite.STYLE_CLASS_DESTRUCTIVE_ACTION);
+            remove_user_button.add_css_class (Granite.CssClass.DESTRUCTIVE);
             remove_user_button.clicked.connect (() => remove_user ());
 
             var remove_lock = new Gtk.Image.from_icon_name ("changes-prevent-symbolic") {

src/Widgets/PasswordEditor.vala

@@ -50,7 +50,7 @@ namespace SwitchboardPlugUserAccounts.Widgets {
             pw_levelbar.add_offset_value ("full", 100.0);
 
             pw_error_revealer = new ErrorRevealer ("."); // Pango needs a non-null string to set markup
-            pw_error_revealer.label_widget.add_css_class (Granite.STYLE_CLASS_WARNING);
+            pw_error_revealer.label_widget.add_css_class (Granite.CssClass.WARNING);
 
             confirm_entry = new Granite.ValidatedEntry () {
                 sensitive = false,
@@ -62,7 +62,7 @@ namespace SwitchboardPlugUserAccounts.Widgets {
             };
 
             confirm_entry_revealer = new ErrorRevealer (".");
-            confirm_entry_revealer.label_widget.add_css_class (Granite.STYLE_CLASS_ERROR);
+            confirm_entry_revealer.label_widget.add_css_class (Granite.CssClass.ERROR);
 
             var show_pw_check = new Gtk.CheckButton.with_label (_("Show passwords"));