sudo apt-get install git libasound-dev libspeexdsp-dev libgtest-dev libtool automake libdbus-1-dev libudev-dev g++ ladspa-sdk libsndfile-dev

On Trusty:

apt-get install libsbc-dev

Pre-Trusty:

install libsbc 1.1 manually by downloading and compiling the tarball from http://www.bluez.org/sbc-11 (I couldn't find a package for Precise). 

ini parser.

git clone https://github.com/ndevilla/iniparser.git
cd iniparser
make
sudo cp libiniparser.* /usr/local/lib
sudo cp src/dictionary.h src/iniparser.h /usr/local/include
sudo chmod 644 /usr/local/include/dictionary.h /usr/local/include/iniparser.h
sudo chmod 644 /usr/local/lib/libiniparser.a
sudo chmod 755 /usr/local/lib/libiniparser.so.0

gtest.

cd /usr/src/gtest
sudo apt-get install cmake
sudo cmake .
sudo make
sudo chmod 644 *.a
sudo cp *.a /usr/local/lib

webrtc-audio-processing

wget http://freedesktop.org/software/pulseaudio/webrtc-audio-processing/webrtc-audio-processing-0.3.tar.xz
tar xvf webrtc-audio-processing-0.3.tar.xz
Apply change-header-location.patch 

webrtc-audio-processing-0.3
./configure
make
sudo make install

Build/install cras.

git clone https://chromium.googlesource.com/chromiumos/third_party/adhd
cd adhd/cras
./git_prepare.sh
./configure --prefix=/usr
make -j33 check
sudo make install

mkdir /var/run/cras
chown $USER /var/run/cras
If you see some build errors on 'snd_pcm_chmap_query_t', it means that you need newer version of alsa-lib. 1.0.27 or higher is required to build cras.

Confiugre/build Chrome.

Follow instruction on wiki for getting and building chrome.

cd chromium/src

GYP_GENERATORS="ninja" ./build/gyp_chromium -Duse_cras=1

ninja -C out/Release chrome

Start cras and chrome.

cd adhd/cras

src/cras

cd chromium/src

./out/Release/chrome --use-cras