Do not fail on errors stored in session

If there is user error stored in session, it would be treated as session
startup error, what is wrong.

Fixes #12229

Signed-off-by: Michal Čihař <michal@cihar.com>

ChangeLog

@@ -18,6 +18,7 @@ phpMyAdmin - ChangeLog
 - issue #12192 Avoid storing full error data in session
 - issue #12082 Fixed export of ARCHIVE tables with keys
 - issue #11565 Add session reload for config authentication
+- issue #12229 Do not fail on errors stored in session
 
 4.6.1 (2016-05-02)
 - issue #12120 PMA_Util not found in insert_edit.lib.php

libraries/ErrorHandler.php

@@ -80,11 +80,15 @@ class ErrorHandler
     /**
      * returns array with all errors
      *
+     * @param $check bool Whether to check for session errors
+     *
      * @return Error[]
      */
-    public function getErrors()
+    public function getErrors($check=true)
     {
-        $this->checkSavedErrors();
+        if ($check) {
+            $this->checkSavedErrors();
+        }
         return $this->errors;
     }
 
@@ -108,7 +112,7 @@ class ErrorHandler
      */
     public function sliceErrors($count)
     {
-        $errors = $this->getErrors();
+        $errors = $this->getErrors(false);
         $this->errors = array_splice($errors, 0, $count);
         return array_splice($errors, $count);
     }
@@ -385,11 +389,13 @@ class ErrorHandler
     /**
      * return count of errors
      *
+     * @param $check bool Whether to check for session errors
+     *
      * @return integer number of errors occurred
      */
-    public function countErrors()
+    public function countErrors($check=true)
     {
-        return count($this->getErrors());
+        return count($this->getErrors($check));
     }
 
     /**

libraries/session.inc.php

@@ -99,12 +99,12 @@ $session_name = 'phpMyAdmin';
 
 // on first start of session we check for errors
 // f.e. session dir cannot be accessed - session file not created
-$orig_error_count = $GLOBALS['error_handler']->countErrors();
+$orig_error_count = $GLOBALS['error_handler']->countErrors(false);
 
 $session_result = session_start();
 
 if ($session_result !== true
-    || $orig_error_count != $GLOBALS['error_handler']->countErrors()
+    || $orig_error_count != $GLOBALS['error_handler']->countErrors(false)
 ) {
     setcookie($session_name, '', 1);
     $errors = $GLOBALS['error_handler']->sliceErrors($orig_error_count);