API Set extension hook implementation visibility to protected

code/FrameworkTestRole.php

@@ -16,7 +16,7 @@ class FrameworkTestRole extends DataExtension
         'FavouritePage' => 'SilverStripe\\CMS\\Model\\SiteTree',
     );
 
-    public function updateCMSFields(FieldList $fields)
+    protected function updateCMSFields(FieldList $fields)
     {
         $fields->addFieldToTab(
             'Root.Main',

code/elemental/ElementContentExtension.php

@@ -40,12 +40,12 @@ class ElementContentExtension extends Extension
         }
     }
 
-    public function updateCMSCompositeValidator(CompositeValidator $compositeValidator)
+    protected function updateCMSCompositeValidator(CompositeValidator $compositeValidator)
     {
         $compositeValidator->addValidator(new RequiredFields(['Title', 'MyPageID', 'MyFile']));
     }
 
-    public function updateCMSFields(FieldList $fields)
+    protected function updateCMSFields(FieldList $fields)
     {
         $fields->removeByName('HTML');
         $fields->addFieldToTab('Root.Main', TextField::create('MyField', 'My Field'));

code/elemental/NumericFieldExtension.php

@@ -10,7 +10,7 @@ use SilverStripe\Core\Extension;
  */
 class NumericFieldExtension extends Extension
 {
-    public function updateValidationResult($result, $validator)
+    protected function updateValidationResult($result, $validator)
     {
         if ($this->owner->Value() == 1) {
             $validator->validationError($this->owner->getName(), 'This field cannot be 1');

code/linkfield/Extensions/CompanyExtension.php

@@ -34,7 +34,7 @@ class CompanyExtension extends Extension
         'ManyCompanyWebSiteLink',
     ];
 
-    public function updateCMSFields(FieldList $fields)
+    protected function updateCMSFields(FieldList $fields)
     {
         $fields->removeByName(['CompanyWebSiteLinkID', 'ManyCompanyWebSiteLinkID']);
 

code/linkfield/Extensions/ElementContentExtension.php

@@ -37,7 +37,7 @@ class ElementContentExtension extends Extension
         'ManyLinks',
     ];
 
-    public function updateCMSFields($fields)
+    protected function updateCMSFields($fields)
     {
         $fields->removeByName(['OneLinkID', 'ManyLinks']);
         $fields->addFieldsToTab(

code/linkfield/Extensions/LinkPageExtension.php

@@ -36,7 +36,7 @@ class LinkPageExtension extends Extension
         'HasManyLinks',
     ];
 
-    public function updateCMSFields(FieldList $fields)
+    protected function updateCMSFields(FieldList $fields)
     {
         $fields->removeByName(['Content', 'HasOneLinkID', 'HasManyLinksID']);