Coding Standards: Use strict type check for in_array() and array_search() where strings are involved.

This reduces the number of `WordPress.PHP.StrictInArray.MissingTrueStrict` issues from 486 to 50.

Includes minor code layout fixes for better readability.

See #49542.

git-svn-id: https://develop.svn.wordpress.org/trunk@47550 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/includes/screen.php

@@ -131,7 +131,7 @@ function meta_box_prefs( $screen ) {
 				printf(
 					'<label for="%1$s-hide"><input class="hide-postbox-tog" name="%1$s-hide" type="checkbox" id="%1$s-hide" value="%1$s" %2$s />%3$s</label>',
 					esc_attr( $box['id'] ),
-					checked( in_array( $box['id'], $hidden ), false, false ),
+					checked( in_array( $box['id'], $hidden, true ), false, false ),
 					$widget_title
 				);
 			}