Responsive grid cleanup

This CL renames some of the variables to keep it consistent across the code. It removes workarounds that were made to facilitate easy code reviews without breaking the tests.
It is a cleanup of the responsive grid feature.

Bug: 299889733
Flag: ACONFIG com.android.launcher3.enable_responsive_workspace TEAMFOOD
Test: CalculatedAllAppsSpecTest
Test: CalculatedFolderSpecTest
Test: CalculatedHotseatSpecTest
Test: CalculatedWorkspaceSpecTest
Test: AllAppsSpecsTest
Test: FolderSpecTest
Test: HotseatSpecsTest
Test: WorkspaceSpecsTest
Change-Id: I198fadfbcfc0d1b32a62a3076949b42ee1fbcf33