Remove a redundant option write-file-if-only-changed in bindings
It is always set on everywhere the option is used for >3 years,
and it means we have no hidden dependencies through generated files.
BUG=
650150
Committed:
https://crrev.com/8db1c398f8456c3d0342b97a15747d1cf2ae994c
Cr-Commit-Position: refs/heads/master@{#421482}