Issue #1599618 by droplet, yurtboy: Fixed Remove duplicate array keys.

core/modules/book/book.module

@@ -540,13 +540,12 @@ function _book_add_form_elements(&$form, &$form_state, Node $node) {
     '#collapsed' => TRUE,
     '#group' => 'additional_settings',
     '#attributes' => array(
-      'class' => array('book-form'),
+      'class' => array('book-outline-form'),
     ),
     '#attached' => array(
       'js' => array(drupal_get_path('module', 'book') . '/book.js'),
     ),
     '#tree' => TRUE,
-    '#attributes' => array('class' => array('book-outline-form')),
   );
   foreach (array('menu_name', 'mlid', 'nid', 'router_path', 'has_children', 'options', 'module', 'original_bid', 'parent_depth_limit') as $key) {
     $form['book'][$key] = array(

core/modules/file/file.field.inc

@@ -587,10 +587,9 @@ function file_field_widget_process($element, &$form_state, $form) {
   // Add the description field if enabled.
   if (!empty($instance['settings']['description_field']) && $item['fid']) {
     $element['description'] = array(
-      '#type' => 'textfield',
+      '#type' => variable_get('file_description_type', 'textfield'),
       '#title' => t('Description'),
       '#value' => isset($item['description']) ? $item['description'] : '',
-      '#type' => variable_get('file_description_type', 'textfield'),
       '#maxlength' => variable_get('file_description_length', 128),
       '#description' => t('The description may be used as the label of the link to the file.'),
     );

core/modules/system/lib/Drupal/system/Tests/Batch/PercentagesUnitTest.php

@@ -40,8 +40,6 @@ function setUp() {
       '33' => array('total' => 3, 'current' => 1),
       // 2/3 is closer to 67% than to 66%.
       '67' => array('total' => 3, 'current' => 2),
-      // A full 3/3 should equal 100%.
-      '100' => array('total' => 3, 'current' => 3),
       // 1/199 should round up to 1%.
       '1' => array('total' => 199, 'current' => 1),
       // 198/199 should round down to 99%.

core/modules/system/lib/Drupal/system/Tests/Form/FormTest.php

@@ -75,7 +75,7 @@ function testRequiredFields() {
     $elements['radios']['element'] = array('#title' => $this->randomName(), '#type' => 'radios', '#options' => array('' => t('None'), $this->randomName(), $this->randomName(), $this->randomName()));
     $elements['radios']['empty_values'] = $empty_arrays;
 
-    $elements['checkbox']['element'] = array('#title' => $this->randomName(), '#type' => 'checkbox', '#required' => TRUE, '#title' => $this->randomName());
+    $elements['checkbox']['element'] = array('#title' => $this->randomName(), '#type' => 'checkbox', '#required' => TRUE);
     $elements['checkbox']['empty_values'] = $empty_checkbox;
 
     $elements['checkboxes']['element'] = array('#title' => $this->randomName(), '#type' => 'checkboxes', '#options' => array($this->randomName(), $this->randomName(), $this->randomName()));