Reorder sdk/android/BUILD.gn.
Reorder sdk/android/BUILD.gn.

sdk/android/BUILD.gn has grown quite big and some structure is needed.
Since git blame history was already disturbed by a recent CL, this
is a good moment to do this.

This CL doesn't include any functional changes, it just reorders
targets.

Bug: webrtc:9048
Change-Id: I339ccb0da40fdc50b3f3f3b6b085a8cf0f591a1b
Reviewed-on: https://webrtc-review.googlesource.com/90046
Commit-Queue: Sami Kalliomäki <b9debeb8943b89663e00c95863751401cba91c9a@webrtc.org>
Reviewed-by: Paulina Hensman <8716904445b72e60995625bd0c8aafd9b5269e8a@webrtc.org>
Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#24084}
TimothyGu/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc,ShiftMediaProject/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc