bug #1859460, prevent an empty target_db field to produce a failure, thanks to windkiel

tbl_move_copy.php

@@ -28,6 +28,14 @@ PMA_DBI_select_db($db);
 
 $goto = $cfg['DefaultTabTable'];
 
+/** 
+ * $_REQUEST['target_db'] could be empty in case we came from an input field 
+ * (when there are many databases, no drop-down)
+ */
+if (empty($_REQUEST['target_db'])) {
+    $_REQUEST['target_db'] = $db;
+}
+
 /**
  * A target table name has been sent to this script -> do the work
  */

tbl_operations.php

@@ -211,7 +211,7 @@ unset($columns);
     <legend><?php echo $strMoveTable; ?></legend>
 <?php if ($GLOBALS['PMA_List_Database']->count() > $GLOBALS['cfg']['MaxDbList']) {
 ?>
-    <input type="text" maxlength="100" size="30" name="target_db" />
+    <input type="text" maxlength="100" size="30" name="target_db" value="<?php echo htmlspecialchars($GLOBALS['db']); ?>"/>
 <?php
     } else {
 ?>
@@ -370,7 +370,7 @@ if (isset($auto_increment) && strlen($auto_increment) > 0
     <legend><?php echo $strCopyTable; ?></legend>
 <?php if ($GLOBALS['PMA_List_Database']->count() > $GLOBALS['cfg']['MaxDbList']) {
 ?>
-    <input type="text" maxlength="100" size="30" name="target_db" />
+    <input type="text" maxlength="100" size="30" name="target_db" value="<?php echo htmlspecialchars($GLOBALS['db']); ?>"/>
 <?php
     } else {
 ?>