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- Remove dependencies on the offlinepages package by passing in an
ObservableSupplier for whether or not prefetch is enabled.

- Remove dependencies on DownloadSettings (which has dependencies that
cannot be moved yet) by passing in a Callback<Context> to launch the
settings screen.

- Remove a dependency on the OfflineContentAggregatorFactory (which
should stay as glue code) by passing in the OfflineContentProvider
interface.

Bug: 1046032
Change-Id: I5d8935661be63e452f08578f18cc33ed735b0536
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2023505
Commit-Queue: David Trainor <dtrainor@chromium.org>
Reviewed-by: Shakti Sahu <shaktisahu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#735767}