Deserialize build dependency around generate_top_domains_for_edit_distance

This is to improve build throughput around generate_top_domains_for_edit_distance by
extracting generated code compilation task independent build target with empty public headers.

Without this CL, build time of obj/chrome/browser/browser/about_flags.o is 57.0s and build trace become like below:
https://chromium-build-stats.appspot.com/ninja_log/upload/ninja_log.EZEgHQkLbX0vpYgBWXcHxRpPp5Lac9I6hVxVjtLpQ08=.gz/trace_sort_by_end.html

With this CL, build time of obj/chrome/browser/browser/about_flags.o is 45.2s and build trace become like below:
https://chromium-build-stats.appspot.com/ninja_log/upload/ninja_log.BM1PZ0eW8JIoMy7WVaOiLe4ogvACUH8pynodDBySeuM=.gz/trace_sort_by_end.html

Dependency to //net is removed by this CL.

Note:
* chrome/browser/ui/BUILD.gn: removed dependency is not used for this target

Bug: 937723
Change-Id: I5d4f0803b66626e1c5ae321cbed4b70b8461928f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1498797
Commit-Queue: Takuto Ikuta <tikuta@chromium.org>
Auto-Submit: Takuto Ikuta <tikuta@chromium.org>
Reviewed-by: Nico Weber <thakis@chromium.org>
Reviewed-by: Peter Kasting <pkasting@chromium.org>
Cr-Commit-Position: refs/heads/master@{#637504}
6 files changed