Only output Save Changes in My Sites when a user is a member of more than one site.

The conditional also checks for the existence of filters that may otherwise alter the HTML in My Sites to include extra form inputs for these users. If a filter is in use, the Save Changes button will display.

Props @Oxymoron, @obenland.
Fixes #32645.


git-svn-id: https://develop.svn.wordpress.org/trunk@33080 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/my-sites.php

@@ -113,9 +113,13 @@ else :
 		echo "</li>";
 	}?>
 	</ul>
-	<input type="hidden" name="action" value="updateblogsettings" />
-	<?php wp_nonce_field( 'update-my-sites' ); ?>
-	<?php submit_button(); ?>
+	<?php
+	if ( count( $blogs ) > 1 || has_action( 'myblogs_allblogs_options' ) || has_filter( 'myblogs_options' ) ) {
+		?><input type="hidden" name="action" value="updateblogsettings" /><?php
+		wp_nonce_field( 'update-my-sites' );
+		submit_button();
+	}
+	?>
 	</form>
 <?php endif; ?>
 	</div>