core: dispatcher test suite and stream completion

[junr03]

Description: This PR adds an initial test suite for the Dispatcher implementation. This test suite is a step in allowing us to iterate on the remaining issues (stream completion, data races, buffer passing, etc) with more confidence. Additionally this PR add logic to track stream state (local and remote) in order to track stream completion state. Once the stream is completed (both local and remote are closed) the stream is removed from the http dispatcher's stream map.

Risk Level: medium - this PR takes into account stream state to modify the http dispatchers stream map.
Testing: added initial suite of unit tests.
Fixes #302

Signed-off-by: Jose Nino jnino@lyft.com

[junr03]

Alright, this is ready for review @goaway. Note per our discussions that the implementation detail of how this PR tracks stream completion state (via local booleans right now) is subject to change once we merge envoyproxy/envoy#7752. However, the test suite is completely agnostic of this fact.

[junr03]

This PR depends on and is currently failing because this Envoy PR has not merged. As soon as that PR merges this PR should point to Envoy upstream master and get merged.

[stale]

This pull request has been automatically marked as stale because it has not had activity in the last 7 days. It will be closed in 7 days if no further activity occurs. Please feel free to give a status update now, ping for review, or re-open when it's ready. Thank you for your contributions!

[junr03]

@goaway this is up-to-date. Do you mind reviewing?

[goaway]

looks great!