Folder and FolderIcon are UI objects and can talk to each other directly.
FolderInfo changes are already propogated via model callbacks, and doesn't need a separate listener pattern.
Bug: 398791288
Flag: EXEMPT bugfix
Test: atest FolderTest
Change-Id: Iefd47b8ea12a8ecaf34211a3d908220a0e999187
Also migrating some other tests that have been verified
Test: SysUI studio
Test: atest NexusLauncherRoboTests
Flag: TEST_ONLY
Change-Id: I072201b8e7b98945ca88657fe813fef4727f16e4