Providing a way to access icon cache without LauncherAcitivtiyInfo.
This allows fetching LauncherActivityInfo only when required, thus
avoiding system RPC when the icon is already in cache.
Change-Id: I92918c7a0d0d0796e5f7b70d4ecb6787c52c6600
of getting it from LauncherAppState
This follows the design of other managers and makes it easier to access it
from other processes and non-ui thread.
Bug: 33032833
Change-Id: I8ad82ae5b6cc47bae885f9896985675c7dd0d5b8