bluetooth: Basic Web Bluetooth Fuzzer

Adds basic structure of the fuzzer, a base template and some tests.

The fuzzer in this file uses two variations of calls to requestDevice to
generate a random sequence of calls. It then replaces instances of
'TRANSFORM_REQUEST_DEVICE_OPTIONS' with object with a single filter with a
single random service.

BUG=570049

Review-Url: https://codereview.chromium.org/2166463002
Cr-Commit-Position: refs/heads/master@{#406940}
12 files changed