Order IMEs and subtype by IME name and ID only

This modifies the comparison of ImeSubtypeListItem list item to only
take into account the IME name and IME id, and thus ignoring the subtype
name, and whether this is the same as the system language or locale.

This allows the order specified by the IME app to be kept as-is.

Flag: android.view.inputmethod.ime_switcher_revamp
Test: atest InputMethodSubtypeSwitchingControllerTest
Bug: 311791923
Fix: 283046933
Change-Id: I2fba8c0ac6e756539deb433a77a8d647a30134ab