ComboBox:Clearable

Build 2281 on feat-combobox
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Baseline History
Build 22819e9ee69
Current build. There are unaccepted changes, so build 2180 is still the baseline.
Build 2180d0ed1cb current baseline
Accepted by Andrey Yamanov.
Build 2177a5b3208
Auto-accepted
Commenting is disabled because there's a newer build on this branch