Add support for different container and space calculation logic.

This CL includes
	- Taskbar container enum class and interface for container to calculate their space needed.
        - Inits and getter of util classes in taksbar activity context.
        - Taskbar Icons specs not have default margins and minimum touch target specs
	- Updates to the test
        - Logic for calculating the space needed for taskbar container

Test: Presubmit
Bug: 341146605
Flag: com.android.launcher3.enable_taskbar_customization
Change-Id: I89e9d521476902a9027f6fd0cebdc2690b2e5f31