Remove manual JNI registration functions from android/compositor

JNI method registration is now automatic. This change removes manual
registration methods in android/compositor.

BUG=740208

Change-Id: I18ac4a41b60fe0c347eeedd379b370affc826a38
Reviewed-on: https://chromium-review.googlesource.com/563826
Commit-Queue: Matthew Jones <mdjones@chromium.org>
Reviewed-by: David Trainor <dtrainor@chromium.org>
Cr-Commit-Position: refs/heads/master@{#487112}
21 files changed