v1.10.0-beta.2 - HTTP/2 client beta release 2

This is a BETA RELEASE of our HTTP/2 client. As it is difficult for us to test our client against all possible situations. The beta release is meant for people to experiment and try our HTTP/2 client and report what does and does not work. This beta branch is synced with our main branch at least once per (beta) release.

Please help us test our HTTP/2 implementation. Open an issue and tag @marty1885 if you found any.

Comment on our compatibility tracker if you like. This allows us to gather a list of known working sites :)

BR, Martin Chang

Fixes

• Fix underflow in our client's HTTP/2 flow control
  • In practice, this fixes server disconnecting due to client sending too much data at once when there's a large body

Changes

• Merge with latest master
• Revised stream resumption logic to avoid edge cases leading to larger then necessary latency
• Better filtering for HTTP smuggling/desync
• Proactively send buffered HTTP/2 frames to reduce reallocation

Limitations

Please open an issue if you need any of them.

• No H2C (HTTP/2 over cleartext) support
• Technically supports handling server push. But no API to expose it to the user yet
• Does not support setting HTTP request dependency and priority
• Does not support trailers