Add two unit tests for Android AppRTCDemo.

First unit test will create peer connection client, run
for a few second, close it and verify that there were
no any errors and local video was rendered.

Second unit test will run peer connection in a loopback mode.

To run the test from command line install AppRTCDemoTest.apk
and execute the command:
adb shell am instrument -w org.appspot.apprtc.test/android.test.InstrumentationTestRunner

R=jiayl@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/33609004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@7991 4adac7df-926f-26a2-2b94-8c16560cd09d
8 files changed