This introduces basic tracing enabled in our tests.
What is captured:
- network resources;
- snapshots at the start of most actions;
- snapshot after the test failure.
How this integrates with test runner:
- context fixture calls private method context._initSnapshotter() and uses Tracer to trace all events;
- all tests share a single test-results/trace-storage directory to store blobs;
- each test has its own trace file.
- npm run show-trace opens a bare-minimum trace viewer that renders snapshots.
Root index.js is only used for local development, so
assuming dev mode there is fine. This way we do not have
to worry about calling setUnderTest early enough.
