When updating src/net/base/effective_tld_names.dat:

1. Build tld_cleanup.exe (the "(net)" > "tld_cleanup" project)
2. Run it (no arguments needed), typically from src/chrome/Release or
   src/chrome/Debug. It will re-generate
   src/net/base/effective_tld_names.gperf.
3. Run gperf on the new effective_tld_names.gperf:
     gperf -a -L "C++" -C -c -o -t -k '*' -NFindDomain -D -m 5 \
        effective_tld_names.gperf > effective_tld_names.cc
   It will produce a new effective_tld_names.cc.
4. Check in the updated effective_tld_names.dat, effective_tld_names.gperf,
   and effective_tld_names.cc together.