Grid Picker Selection Animation Fix (1/2)

Fix grid picker selection animation issue, due to comparison issues in
diff util.

Bug: 273336388
Test: Manually verified that grid picker, color picker, and quick
affordance picker selection animation function correctly. Tested with
print statements to verify diff util functions as intended. Updated
field types in grid view model test.

Change-Id: If48da6985ca99e254fbe511f2062a32e946883c9