diff --git a/core/modules/block/lib/Drupal/block/Tests/BlockRenderOrderTest.php b/core/modules/block/lib/Drupal/block/Tests/BlockRenderOrderTest.php
index 0521aa9..5941859 100644
--- a/core/modules/block/lib/Drupal/block/Tests/BlockRenderOrderTest.php
+++ b/core/modules/block/lib/Drupal/block/Tests/BlockRenderOrderTest.php
@@ -43,7 +43,7 @@ function setUp() {
    */
   function testBlockRenderOrder() {
     // Enable test blocks and place them in the same region.
-    $region = 'header';
+    $region = 'header_second';
     $test_blocks = array(
       'stark_powered' => array(
         'weight' => '-3',
diff --git a/core/modules/block/lib/Drupal/block/Tests/BlockSystemBrandingTest.php b/core/modules/block/lib/Drupal/block/Tests/BlockSystemBrandingTest.php
index 192d8fc..9a74e94 100644
--- a/core/modules/block/lib/Drupal/block/Tests/BlockSystemBrandingTest.php
+++ b/core/modules/block/lib/Drupal/block/Tests/BlockSystemBrandingTest.php
@@ -40,7 +40,7 @@ public function setUp() {
       ->set('slogan', 'Community plumbing')
       ->save();
     // Add the system branding block to the page.
-    $this->drupalPlaceBlock('system_branding_block', array('region' => 'header', 'id' => 'site-branding'));
+    $this->drupalPlaceBlock('system_branding_block', array('region' => 'header_second', 'id' => 'site-branding'));
   }
 
   /**
diff --git a/core/modules/block/lib/Drupal/block/Tests/BlockTest.php b/core/modules/block/lib/Drupal/block/Tests/BlockTest.php
index e7b99e1..b6e9101 100644
--- a/core/modules/block/lib/Drupal/block/Tests/BlockTest.php
+++ b/core/modules/block/lib/Drupal/block/Tests/BlockTest.php
@@ -104,7 +104,7 @@ function testBlock() {
     $block['id'] = 'system_powered_by_block';
     $block['settings[label]'] = $this->randomName(8);
     $block['theme'] = \Drupal::config('system.theme')->get('default');
-    $block['region'] = 'header';
+    $block['region'] = 'header_second';
 
     // Set block title to confirm that interface works and override any custom titles.
     $this->drupalPostForm('admin/structure/block/add/' . $block['id'] . '/' . $block['theme'], array('settings[label]' => $block['settings[label]'], 'id' => $block['id'], 'region' => $block['region']), t('Save block'));
@@ -224,7 +224,7 @@ function testHideBlockTitle() {
    *   - delta: The block's delta key.
    * @param string $region
    *   The machine name of the theme region to move the block to, for example
-   *   'header' or 'sidebar_first'.
+   *   'header_second' or 'sidebar_first'.
    */
   function moveBlockToRegion(array $block, $region) {
     // Set the created block to a specific region.
@@ -262,8 +262,9 @@ function testBlockRehash() {
     $block = array();
     $block['id'] = 'test_cache';
     $block['theme'] = \Drupal::config('system.theme')->get('default');
-    $block['region'] = 'header';
-    $block = $this->drupalPlaceBlock('test_cache', array('region' => 'header'));
+    $block['region'] = 'header_second';
+    $block = $this->drupalPlaceBlock('test_cache', array('region' => 'header_second'));
+    $block = $this->drupalPlaceBlock('test_cache', array('region' => 'header_second'));
 
     // Our test block's caching should default to DRUPAL_CACHE_PER_ROLE.
     $settings = $block->get('settings');
diff --git a/core/modules/block/lib/Drupal/block/Tests/BlockUiTest.php b/core/modules/block/lib/Drupal/block/Tests/BlockUiTest.php
index 356d480..27f82ad 100644
--- a/core/modules/block/lib/Drupal/block/Tests/BlockUiTest.php
+++ b/core/modules/block/lib/Drupal/block/Tests/BlockUiTest.php
@@ -110,8 +110,8 @@ function testBlockAdminUiPage() {
       $this->assertTrue((string) $element[0] == $label, 'The "' . $label . '" block title is set inside the ' . $values['settings']['region'] . ' region.');
       // Look for a test block region select form element.
       $this->assertField('blocks[' . $values['settings']['id'] . '][region]', 'The block "' . $values['label'] . '" has a region assignment field.');
-      // Move the test block to the header region.
-      $edit['blocks[' . $values['settings']['id'] . '][region]'] = 'header';
+      // Move the test block to the header_second region.
+      $edit['blocks[' . $values['settings']['id'] . '][region]'] = 'header_second';
       // Look for a test block weight select form element.
       $this->assertField('blocks[' . $values['settings']['id'] . '][weight]', 'The block "' . $values['label'] . '" has a weight assignment field.');
       // Change the test block's weight.
@@ -122,8 +122,8 @@ function testBlockAdminUiPage() {
       // Check if the region and weight settings changes have persisted.
       $this->assertOptionSelected(
         'edit-blocks-' . $values['settings']['id']  . '-region',
-        'header',
-        'The block "' . $label . '" has the correct region assignment (header).'
+        'header_second',
+        'The block "' . $label . '" has the correct region assignment (header_second).'
       );
       $this->assertOptionSelected(
         'edit-blocks-' . $values['settings']['id']  . '-weight',
diff --git a/core/themes/bartik/config/schema/block.block.bartik.branding.schema.yml b/core/themes/bartik/config/schema/block.block.bartik.branding.schema.yml
new file mode 100644
index 0000000..57cd696
--- /dev/null
+++ b/core/themes/bartik/config/schema/block.block.bartik.branding.schema.yml
@@ -0,0 +1,92 @@
+# Schema for the configuration files of the Block module.
+
+block.block.bartik.branding:
+  type: mapping
+  label: 'Block'
+  mapping:
+    id:
+      type: string
+      label: 'ID'
+    uuid:
+      type: string
+      label: 'UUID'
+    theme:
+      type: string
+      label: 'Theme'
+    region:
+      type: string
+      label: 'Region'
+    weight:
+      type: integer
+      label: 'Weight'
+    module:
+      type: string
+      label: 'Module'
+    status:
+      type: boolean
+      label: 'Status'
+    visibility:
+      type: mapping
+      label: 'Visibility settings'
+      mapping:
+        path:
+          type: mapping
+          label: 'Pages'
+          mapping:
+            visibility:
+              type: integer
+              label: 'Visibility'
+            pages:
+              type: string
+              label: 'Show block on specific pages'
+        role:
+          type: mapping
+          label: 'Roles'
+          mapping:
+            roles:
+              type: sequence
+              label: 'Show block for specific roles'
+              sequence:
+                - type: string
+                  label: 'Role'
+        node_type:
+          type: mapping
+          label: 'Content types'
+          mapping:
+            types:
+              type: sequence
+              label: 'Show block for specific content types'
+              sequence:
+               - type: string
+                 label: 'Node type'
+    plugin:
+      type: string
+      label: 'Plugin'
+    settings:
+      type: mapping
+      label: 'Block settings'
+      mapping:
+        label:
+          type: label
+          label: 'Description'
+        label_display:
+          type: string
+          label: 'Display title'
+        cache:
+          type: integer
+          label: 'Cache'
+        status:
+          type: boolean
+          label: 'Status'
+        info:
+          type: label
+          label: 'Admin info'
+        view_mode:
+          type: string
+          label: 'View mode'
+        module:
+          type: string
+          label: 'Module'
+    langcode:
+      type: string
+      label: 'Default language'
diff --git a/core/themes/stark/config/schema/block.block.stark.branding.schema.yml b/core/themes/stark/config/schema/block.block.stark.branding.schema.yml
new file mode 100644
index 0000000..57cd696
--- /dev/null
+++ b/core/themes/stark/config/schema/block.block.stark.branding.schema.yml
@@ -0,0 +1,92 @@
+# Schema for the configuration files of the Block module.
+
+block.block.bartik.branding:
+  type: mapping
+  label: 'Block'
+  mapping:
+    id:
+      type: string
+      label: 'ID'
+    uuid:
+      type: string
+      label: 'UUID'
+    theme:
+      type: string
+      label: 'Theme'
+    region:
+      type: string
+      label: 'Region'
+    weight:
+      type: integer
+      label: 'Weight'
+    module:
+      type: string
+      label: 'Module'
+    status:
+      type: boolean
+      label: 'Status'
+    visibility:
+      type: mapping
+      label: 'Visibility settings'
+      mapping:
+        path:
+          type: mapping
+          label: 'Pages'
+          mapping:
+            visibility:
+              type: integer
+              label: 'Visibility'
+            pages:
+              type: string
+              label: 'Show block on specific pages'
+        role:
+          type: mapping
+          label: 'Roles'
+          mapping:
+            roles:
+              type: sequence
+              label: 'Show block for specific roles'
+              sequence:
+                - type: string
+                  label: 'Role'
+        node_type:
+          type: mapping
+          label: 'Content types'
+          mapping:
+            types:
+              type: sequence
+              label: 'Show block for specific content types'
+              sequence:
+               - type: string
+                 label: 'Node type'
+    plugin:
+      type: string
+      label: 'Plugin'
+    settings:
+      type: mapping
+      label: 'Block settings'
+      mapping:
+        label:
+          type: label
+          label: 'Description'
+        label_display:
+          type: string
+          label: 'Display title'
+        cache:
+          type: integer
+          label: 'Cache'
+        status:
+          type: boolean
+          label: 'Status'
+        info:
+          type: label
+          label: 'Admin info'
+        view_mode:
+          type: string
+          label: 'View mode'
+        module:
+          type: string
+          label: 'Module'
+    langcode:
+      type: string
+      label: 'Default language'