Update preprocessData code and types to support new profiling marks

[taneliang]

Steps

• Complete Add user timing marks for scheduling profiler tool react#11 to an extent where we can export performance profiles containing marks
• Define new V2 data types to support new marks
• Create preprocessDataV2 to support new data types and new marks

Acceptance criteria

• A new ReactProfilerDataV2 and other V2 types should be created to support the new profiling marks.
• preprocessDataV2 should transform a raw profiling JSON into a correct ReactProfilerDataV2
• No parsing errors in console on page load
• Neat code, possibly tested (blocked by Set up testing infrastructure #14)