[C++] Namespace collisions with protobuf 3.15 #27582
Description
We define pb as a namespace alias in the flight sources. This conflicts with protobuf starting to introduce it as its global namespace alias.
Reporter: Uwe Korn / @xhochy
Assignee: Uwe Korn / @xhochy
PRs and other links:
Note: This issue was originally created as ARROW-11724. Please see the migration documentation for further details.