commit ea9cd342683e9aa4dff80634ace529e4f9fc5087
Author: brantwynn <brant.wynn@acquia.com>
Date:   Sun May 19 19:21:10 2013 -0700

    1998582-new_changes

diff --git a/core/modules/views/views.module b/core/modules/views/views.module
index 74e093d..fd169d7 100644
--- a/core/modules/views/views.module
+++ b/core/modules/views/views.module
@@ -1821,17 +1821,24 @@ function views_cache_get($cid, $use_language = FALSE) {
 /**
  * Implement hook_form_alter for the views block form.
  *
- * Views sets up its own plugin portions of the block configuration form but
- * assigning machine names is not handled by the plugin so we do this here.
+ * Views overrides block configuration form elements during ViewsBlock:form()
+ * but machine_name assignment is added later by BlockFormController:form()
+ * so we provide an override for the block machine_name here.
  */
 function views_form_block_form_alter(&$form, &$form_state) {
+  // Ensure the block-form being altered is a Views block configuration form.
   if ($form['settings']['module']['#value'] == 'views') {
+    // Unset the machine_name provided by BlockFormController
+    unset($form['machine_name']['#machine_name']['source']);
+    // Load the Views plugin object using form_state array and create a
+    // block machine_name based on the View ID and View Display ID.
     $block_plugin = $form_state['build_info']['callback_object']->getEntity()->getPlugin();
     list($plugin, $delta) = explode(':', $block_plugin->getPluginId());
-    list($name, $displayID) = explode('-', $delta, 2);
-    unset($form['machine_name']['#machine_name']['source']);
-    $form['machine_name']['#default_value'] = 'views_block__' . $name . '_' . $displayID;
+    list($view_id, $display_id) = explode('-', $delta, 2);
+    // Override the Views block's machine_name by providing a default_value.
+    $form['machine_name']['#default_value'] = 'views_block__' . $view_id . '_' . $display_id;
+    // Prevent users from changing the auto-generate block machine_name.
     $form['machine_name']['#access'] = FALSE;
-  } 
+  }
 }