diff -u b/core/modules/book/tests/src/Functional/BookTestTrait.php b/core/modules/book/tests/src/Functional/BookTestTrait.php
--- b/core/modules/book/tests/src/Functional/BookTestTrait.php
+++ b/core/modules/book/tests/src/Functional/BookTestTrait.php
@@ -72,11 +72,11 @@
    * @param $nodes
    *   Nodes that should be in outline.
    * @param $previous
-   *   Previous link node. Defaults to FALSE.
+   *   Previous link node.
    * @param $up
-   *   Up link node. Defaults to FALSE.
+   *   Up link node.
    * @param $next
-   *   Next link node. Defaults to FALSE.
+   *   Next link node.
    * @param array $breadcrumb
    *   The nodes that should be displayed in the breadcrumb.
    */
diff -u b/core/phpcs.xml.dist b/core/phpcs.xml.dist
--- b/core/phpcs.xml.dist
+++ b/core/phpcs.xml.dist
@@ -110,9 +110,6 @@
   <rule ref="Generic.WhiteSpace.DisallowTabIndent"/>
   <rule ref="Generic.Arrays.DisallowLongArraySyntax" />
 
-  <!-- PEAR sniffs -->
-  <rule ref="PEAR.Functions.ValidDefaultValue"/>
-
   <!-- PSR-2 sniffs -->
   <rule ref="PSR2.Classes.PropertyDeclaration">
     <exclude name="PSR2.Classes.PropertyDeclaration.Underscore"/>
@@ -139,6 +136,9 @@
     <severity>0</severity>
   </rule>
 
+  <!-- PEAR sniffs -->
+  <rule ref="PEAR.Functions.ValidDefaultValue"/>
+
   <!-- PSR-2 sniffs -->
   <rule ref="PSR2.Classes.PropertyDeclaration">
     <exclude name="PSR2.Classes.PropertyDeclaration.Underscore"/>