Merge "Make the context page the edited page in EditPages"

diff --combined includes/EditPage.php
index 1f17297,09dc070..5f4c3ae
--- 1/includes/EditPage.php
--- 2/includes/EditPage.php
+++ b/includes/EditPage.php
@@@ -476,7 -476,15 +476,15 @@@ class EditPage 
                $this->mArticle = $article;
                $this->page = $article->getPage(); // model object
                $this->mTitle = $article->getTitle();
-               $this->context = $article->getContext();
+ 
+               // Make sure the local context is in sync with other member variables.
+               // Particularly make sure everything is using the same WikiPage instance.
+               // This should probably be the case in Article as well, but it's
+               // particularly important for EditPage, to make use of the in-place caching
+               // facility in WikiPage::prepareContentForEdit.
+               $this->context = new DerivativeContext( $article->getContext() );
+               $this->context->setWikiPage( $this->page );
+               $this->context->setTitle( $this->mTitle );
  
                $this->contentModel = $this->mTitle->getContentModel();
  
@@@ -3145,22 -3153,16 +3153,22 @@@ ERROR
                        );
                } elseif ( $user->isAnon() ) {
                        if ( $this->formtype != 'preview' ) {
 +                              $returntoquery = array_diff_key(
 +                                      $this->context->getRequest()->getValues(),
 +                                      [ 'title' => true, 'returnto' => true, 'returntoquery' => true ]
 +                              );
                                $out->wrapWikiMsg(
                                        "<div id='mw-anon-edit-warning' class='warningbox'>\n$1\n</div>",
                                        [ 'anoneditwarning',
                                                // Log-in link
                                                SpecialPage::getTitleFor( 'Userlogin' )->getFullURL( [
 -                                                      'returnto' => $this->getTitle()->getPrefixedDBkey()
 +                                                      'returnto' => $this->getTitle()->getPrefixedDBkey(),
 +                                                      'returntoquery' => wfArrayToCgi( $returntoquery ),
                                                ] ),
                                                // Sign-up link
                                                SpecialPage::getTitleFor( 'CreateAccount' )->getFullURL( [
 -                                                      'returnto' => $this->getTitle()->getPrefixedDBkey()
 +                                                      'returnto' => $this->getTitle()->getPrefixedDBkey(),
 +                                                      'returntoquery' => wfArrayToCgi( $returntoquery ),
                                                ] )
                                        ]
                                );