Revert "Adjust build and test scripts for handling ICU prebuilts."

Revert "Remove ICU projects for master-art manifest."

Revert "Update mainline prebuilts to build 6608121."

Revert submission 1343524-art-use-icu-sdk

Bug: 157734636
Bug: 129332183

Reason for revert: Tests failing
Reverted Changes:
I8ae469ade:Adjust build and test scripts for handling ICU pre...
Ia0e5424cf:Remove ICU projects for master-art manifest.
I191a102d6:Update mainline prebuilts to build 6608121.

Change-Id: I40eb44a9de056636353e0e8225445c628581aea8
5 files changed