okhttp: Fix race condition overwriting MAX_CONCURRENT_STREAMS #12548
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What this PR does
This PR fixes a race condition in
OkHttpClientTransportwhereMAX_CONCURRENT_STREAMSsent by the server could be incorrectly overwritten by the client's default initialization.The fix simply reorders the initialization to happen before starting the reader thread, ensuring that any updates from the server are preserved.
Note on Testing
I attempted to add a deterministic reproduction test, but reliably simulating this specific race condition proved difficult without intrusive changes.
I request reviewers to primarily verify the logical correctness of the reordering. I am open to collaborating with the team to develop a suitable test case if required.
Future Work
This PR covers Step 1 (Fixing the race condition) of the plan discussed in #11985.
I plan to follow up with Step 2 (Adding assertions to verify no pending streams exist) in a separate PR.
Part of #11985