refactor: Move functions into FieldDropdown. #8634

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@gonfunko

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✅ e4496dc Author: @gonfunko <go****ko@gmail.com>, <ad****n@google.com>
✅ d053008 Co-Author: @dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
✅ 9cd58e3 Author: @cpcallen <cpc******git@google.com>
✅ 437f6a3 Author: @johnnesky <jo*****ky@gmail.com>, <n***y@google.com>
✅ f57ef73 Co-Author: @BeksOmega <bw*****rg@google.com>
✅ 504de6a Author: @HollowMan6 <ho*****an@opensuse.org>
✅ 23e9011 Author: @UCYT5040 <46662314+UCYT5040@users.noreply.github.com>
✅ 6b3f9a6 Author: @AbhinavKRN <115357208+AbhinavKRN@users.noreply.github.com>
✅ ec8f9c8 Author: @abhinavjha0239 <75026232+abhinavjha0239@users.noreply.github.com>
✅ 6acc583 Author: @BenHenning <bh****ng@google.com>
✅ 4d0fd5d Author: @changminbark <88669927+changminbark@users.noreply.github.com>
✅ 0a6596c Author: @rachel-fenichel <fe****el@google.com>
✅ 6a67400 Author: @riknoll <riknoll@users.noreply.github.com>

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