Apply intensity settings to composed vibration effects

Use the existing maxAmplitude and gamma adjustment values to apply the
relative scaling of default vibration intensity settings and user
settings on top of the PrimitiveEffect#scale value.

As a consequence, the relative scaled amplitude of a OneShot or Waveform
vibration effect should match the scaled PrimitiveEffect#scale value.

Fix: 154089649
Test: atest FrameworksCoreTests:VibrationEffectTest
Change-Id: I3ca0042a42675289a2ed8110c9dc3798055ebf4a