Backport of "examples/player/android: add missing dummy.cpp" into 1.20
requested to merge tpm/gstreamer:backport-mr-2043-into-1.20-android-player-example-update-part2 into 1.20
Backport of !2043 (merged) "examples/player/android: add missing dummy.cpp".
Commits:
- 4a2e0c1f examples/player/android: add missing dummy.cpp