Add check for undefined scale factor fields

This should support stable AIDL parcelabled for HapticGenerator that
does not include the new scale factor float values.

Adding checks for unsupported values to the scale method with coverage
tests.

Bug: 356406686
Bug: 356406324
Test: libvibrator_test
Flag: android.os.vibrator.haptics_scale_v2_enabled
Change-Id: Ic6a0f1610b47208cd9621d43f2c55845575af649