small code refactor - group together some code that should be together

git-svn-id: http://piwigo.org/svn/trunk@3167 68402e56-0260-453c-a942-63ccdbb3a9ee

include/section_init.inc.php

@@ -108,6 +108,7 @@ if (script_basename() == 'picture') // basename without file extention
     }
     else
     {
+      $page['image_id'] = 0; // more work in picture.php
       if ( !empty($matches[2]) )
       {
         $page['image_file'] = $matches[2];
@@ -562,12 +563,6 @@ if (isset($page['chronology_field']))
   initialize_calendar();
 }
 
-if (script_basename() == 'picture'
-    and !isset($page['image_id']) )
-{
-  $page['image_id'] = 0; // more work in picture.php
-}
-
 // add meta robots noindex, nofollow to avoid unnecesary robot crawls
 $page['meta_robots']=array();
 if ( isset($page['chronology_field'])