ToneGenerator: support output sample rates beyond 65535 Hz

Changed type of ToneGenerator::WaveGenerator constructor parameter
samplingRate from unsigned short to uint32_t to permit output
sample rates such as 96000 Hz.

Bug: 33969539
Test: dialer tones work when output sink operates at 96000 Hz
Change-Id: I5551409c467a4fd98ea4d5c9703b120a526a443e
2 files changed