exo: Add display rotation support to Wayland bindings.
exo: Add display rotation support to Wayland bindings.

Send display rotation changes to Wayland clients.

BUG=549781
TEST=manual

Review URL: https://codereview.chromium.org/1778053003

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#380274}

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