Comment 4 for bug 1415321

Origin (regression introduced in Mir 0.10.0):

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revno: 2129 [merge]
fixes bug: https://launchpad.net/bugs/1311699
author: Robert Carr <email address hidden>
committer: Daniel van Vugt <email address hidden>
branch nick: dev
timestamp: Tue 2014-12-09 11:29:51 +0800
message:
  Introduce a transition path to MirEvent 2.0, henceforth MirInputEvent.

  Direct access to MirEvent::type is deprecated, and a new method
  mir_event_get_type is encouraged. For what was mir_event_type_key/motion
  a new type mir_event_type_input will be returned. Client code may call
  mir_event_get_input_event(...) to retreive a "MirInputEvent*" a.k.a.
  MirEvent 2.0.
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