Revert "Build DocumentsUI sources once"

Revert submission 25032702-DocumentsUI-lib

Reason for revert: broke document browsing

Reverted changes: /q/submissionid:25032702-DocumentsUI-lib

Bug: 307873144
Bug: 307882692
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:0d1e2f46a5dde64df8506691afe89efda697a60c)
Merged-In: I5042f5f430f515cfe648156f21f7570e43aabbe6
Change-Id: I5042f5f430f515cfe648156f21f7570e43aabbe6