Add ruby to the list of build dependencies so that WebKit's pretty diff utility

build/install-build-deps.sh

 #!/bin/bash -e
 
 # Copyright (c) 2011 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # Script to install everything needed to build chromium (well, ideally, anyway)
 # See http://code.google.com/p/chromium/wiki/LinuxBuildInstructions
 # and http://code.google.com/p/chromium/wiki/LinuxBuild64Bit
 
@@ skipping 91 matching lines @@
 
 # Packages need for development
 dev_list="apache2.2-bin bison fakeroot flex g++ gperf language-pack-fr
           libapache2-mod-php5 libasound2-dev libbz2-dev libcairo2-dev
           libcups2-dev libdbus-glib-1-dev libgconf2-dev
           libgl1-mesa-dev libglu1-mesa-dev libglib2.0-dev libgnome-keyring-dev
           libgtk2.0-dev libjpeg62-dev libkrb5-dev libnspr4-dev libnss3-dev
           libpam0g-dev libsctp-dev libsqlite3-dev libxslt1-dev libxss-dev
           libxtst-dev mesa-common-dev msttcorefonts patch perl libwww-perl
           php5-cgi pkg-config python python-dev rpm subversion ttf-dejavu-core
-          ttf-kochi-gothic ttf-kochi-mincho wdiff libcurl4-gnutls-dev
+          ttf-kochi-gothic ttf-kochi-mincho wdiff ruby libcurl4-gnutls-dev
           ttf-indic-fonts ttf-thai-tlwg
           $chromeos_dev_list"
 
 # Run-time libraries required by chromeos only
 chromeos_lib_list="libpulse0 libbz2-1.0 libcurl4-gnutls-dev"
 
 # Full list of required run-time libraries
 lib_list="libatk1.0-0 libc6 libasound2 libcairo2 libcups2 libdbus-glib-1-2
           libexpat1 libfontconfig1 libfreetype6 libglib2.0-0 libgnome-keyring0
           libgtk2.0-0 libpam0g libpango1.0-0 libpcre3 libpixman-1-0
@@ skipping 333 matching lines @@
              sed -e 's/[.]so[.][0-9].*/.so/' |
              sort -u); do
     [ "x${i##*/}" = "xld-linux.so" ] && continue
     [ -r "$i" ] && continue
     j="$(ls "$i."* | sed -e 's/.*[.]so[.]\([^.]*\)$/\1/;t;d' |
          sort -n | tail -n 1)"
     [ -r "$i.$j" ] || continue
     sudo ln -s "${i##*/}.$j" "$i"
   done
 fi