Roll to Checkstyle 5.9 and enable Indentation check.

tools/android/checkstyle/chromium-style-5.0.xml

 <?xml version="1.0" encoding="UTF-8"?>
 <!DOCTYPE module PUBLIC "-//Puppy Crawl//DTD Check Configuration 1.3//EN" "http://www.puppycrawl.com/dtds/configuration_1_3.dtd">
 
 <!--
   See installation instructions: https://sites.google.com/a/chromium.org/dev/checkstyle
 -->
 <module name="Checker">
   <property name="severity" value="warning"/>
   <property name="charset" value="UTF-8"/>
   <module name="TreeWalker">
@@ skipping 140 matching lines @@
       <property name="severity" value="error"/>
     </module>
     <module name="ImportOrder">
       <property name="severity" value="error"/>
       <message key="import.ordering" value="Wrong order for {0} import. Use :JavaImportOrganize (ECLIM) or Ctrl+Shift+O (Eclipse) to sort imports"/>
       <property name="groups" value="android, com, dalvik, gov, junit, libcore, net, org, java, javax"/>
       <property name="ordered" value="true"/>
       <property name="option" value="top"/>
       <property name="separated" value="true"/>
     </module>
-    <!-- TODO(aurimas): make indentation an error once https://github.com/checkstyle/checkstyle/issues/255 is fixed. -->
     <module name="Indentation">
-      <property name="severity" value="info"/>
+      <property name="severity" value="error"/>
       <property name="basicOffset" value="4"/>
       <property name="throwsIndent" value="8"/>
+      <property name="lineWrappingIndentation" value="8"/>
     </module>
   </module>
   <module name="FileTabCharacter">
     <property name="severity" value="error"/>
   </module>
   <module name="RegexpSingleline">
     <property name="severity" value="error"/>
     <property name="format" value="[ \t]+$"/>
     <property name="message" value="Trailing whitespace"/>
     </module>
   <module name="RegexpHeader">
     <property name="severity" value="error"/>
     <property name="header" value="^// Copyright 20\d\d The Chromium Authors. All rights reserved.$\n^// Use of this source code is governed by a BSD-style license that can be$\n^// found in the LICENSE file.$"/>
   </module>
 </module>