updated drupal core to 7.51

modules/system/system.install

@@ -196,6 +196,12 @@ function system_requirements($phase) {
     );
   }
 
+  // Test database-specific multi-byte UTF-8 related requirements.
+  $charset_requirements = _system_check_db_utf8mb4_requirements($phase);
+  if (!empty($charset_requirements)) {
+    $requirements['database_charset'] = $charset_requirements;
+  }
+
   // Test PHP memory_limit
   $memory_limit = ini_get('memory_limit');
   $requirements['php_memory_limit'] = array(
@@ -517,6 +523,75 @@ function system_requirements($phase) {
   return $requirements;
 }
 
+/**
+ * Checks whether the requirements for multi-byte UTF-8 support are met.
+ *
+ * @param string $phase
+ *   The hook_requirements() stage.
+ *
+ * @return array
+ *   A requirements array with the result of the charset check.
+ */
+function _system_check_db_utf8mb4_requirements($phase) {
+  global $install_state;
+  // In the requirements check of the installer, skip the utf8mb4 check unless
+  // the database connection info has been preconfigured by hand with valid
+  // information before running the installer, as otherwise we cannot get a
+  // valid database connection object.
+  if (isset($install_state['settings_verified']) && !$install_state['settings_verified']) {
+    return array();
+  }
+
+  $connection = Database::getConnection();
+  $t = get_t();
+  $requirements['title'] = $t('Database 4 byte UTF-8 support');
+
+  $utf8mb4_configurable = $connection->utf8mb4IsConfigurable();
+  $utf8mb4_active = $connection->utf8mb4IsActive();
+  $utf8mb4_supported = $connection->utf8mb4IsSupported();
+  $driver = $connection->driver();
+  $documentation_url = 'https://www.drupal.org/node/2754539';
+
+  if ($utf8mb4_active) {
+    if ($utf8mb4_supported) {
+      if ($phase != 'install' && $utf8mb4_configurable && !variable_get('drupal_all_databases_are_utf8mb4', FALSE)) {
+        // Supported, active, and configurable, but not all database tables
+        // have been converted yet.
+        $requirements['value'] = $t('Enabled, but database tables need conversion');
+        $requirements['description'] = $t('Please convert all database tables to utf8mb4 prior to enabling it in settings.php. See the <a href="@url">documentation on adding 4 byte UTF-8 support</a> for more information.', array('@url' => $documentation_url));
+        $requirements['severity'] = REQUIREMENT_ERROR;
+      }
+      else {
+        // Supported, active.
+        $requirements['value'] = $t('Enabled');
+        $requirements['description'] = $t('4 byte UTF-8 for @driver is enabled.', array('@driver' => $driver));
+        $requirements['severity'] = REQUIREMENT_OK;
+      }
+    }
+    else {
+      // Not supported, active.
+      $requirements['value'] = $t('Not supported');
+      $requirements['description'] = $t('4 byte UTF-8 for @driver is activated, but not supported on your system. Please turn this off in settings.php, or ensure that all database-related requirements are met. See the <a href="@url">documentation on adding 4 byte UTF-8 support</a> for more information.', array('@driver' => $driver, '@url' => $documentation_url));
+      $requirements['severity'] = REQUIREMENT_ERROR;
+    }
+  }
+  else {
+    if ($utf8mb4_supported) {
+      // Supported, not active.
+      $requirements['value'] = $t('Not enabled');
+      $requirements['description'] = $t('4 byte UTF-8 for @driver is not activated, but it is supported on your system. It is recommended that you enable this to allow 4-byte UTF-8 input such as emojis, Asian symbols and mathematical symbols to be stored correctly. See the <a href="@url">documentation on adding 4 byte UTF-8 support</a> for more information.', array('@driver' => $driver, '@url' => $documentation_url));
+      $requirements['severity'] = REQUIREMENT_INFO;
+    }
+    else {
+      // Not supported, not active.
+      $requirements['value'] = $t('Disabled');
+      $requirements['description'] = $t('4 byte UTF-8 for @driver is disabled. See the <a href="@url">documentation on adding 4 byte UTF-8 support</a> for more information.', array('@driver' => $driver, '@url' => $documentation_url));
+      $requirements['severity'] = REQUIREMENT_INFO;
+    }
+  }
+  return $requirements;
+}
+
 /**
  * Implements hook_install().
  */
@@ -532,6 +607,9 @@ function system_install() {
   module_list(TRUE);
   module_implements('', FALSE, TRUE);
 
+  // Ensure the schema versions are not based on a previous module list.
+  drupal_static_reset('drupal_get_schema_versions');
+
   // Load system theme data appropriately.
   system_rebuild_theme_data();
 
@@ -3192,6 +3270,21 @@ function system_update_7080() {
   db_change_field('date_format_locale', 'format', 'format', $spec);
 }
 
+/**
+ * Remove the Drupal 6 default install profile if it is still in the database.
+ */
+function system_update_7081() {
+  // Sites which used the default install profile in Drupal 6 and then updated
+  // to Drupal 7.44 or earlier will still have a record of this install profile
+  // in the database that needs to be deleted.
+  db_delete('system')
+    ->condition('filename', 'profiles/default/default.profile')
+    ->condition('type', 'module')
+    ->condition('status', 0)
+    ->condition('schema_version', 0)
+    ->execute();
+}
+
 /**
  * @} End of "defgroup updates-7.x-extra".
  * The next series of updates should start at 8000.