Added tests for audio effects.

AudioEffectTest.java: tests for base AudioEffect class.
BassBoostTest.java: tests for bass boost effect
EnvReverbTest.java: tests for environmental reverb
PresetReverbTest.java: tests for preset reverb
VirtualizerTest.java: tests for virtualizer
VisualizerTest.java: test for visualizer

There is no requirement on the quality of audio effects or the supported parameter ranges.
The tests just ensure that the platform exposes and responds to all methods in effect APIs.

Change-Id: Ibdd0bf937c30ce000184e0bdf2323655ebf1d839
7 files changed