Always use 1 step as a fallback (#1488490)

installer/index.php

@@ -137,6 +137,15 @@ if ($RCI->configured && empty($_REQUEST['_step'])) {
 
 <ol id="progress">
 <?php
+  $include_steps = array(
+    1 => './check.php',
+    2 => './config.php',
+    3 => './test.php',
+  );
+
+  if (!in_array($RCI->step, array_keys($include_steps))) {
+    $RCI->step = 1;
+  }
 
   foreach (array('Check environment', 'Create config', 'Test config') as $i => $item) {
     $j = $i + 1;
@@ -147,15 +156,8 @@ if ($RCI->configured && empty($_REQUEST['_step'])) {
 </ol>
 
 <?php
-$include_steps = array('', './check.php', './config.php', './test.php');
 
-if ($include_steps[$RCI->step]) {
 include $include_steps[$RCI->step];
-}
-else {
-  header("HTTP/1.0 404 Not Found");
-  echo '<h2 class="error">Invalid step</h2>';
-}
 
 ?>
 </div>

installer/rcube_install.php

@@ -524,7 +524,7 @@ class rcube_install
         '0.5-beta', '0.5', '0.5.1',
         '0.6-beta', '0.6',
         '0.7-beta', '0.7', '0.7.1', '0.7.2',
-        '0.8-beta',
+        '0.8-beta', '0.8-rc',
     ));
     return $select;
   }