tree e04e9f1af71002eb9ab52544f30afc4da9fcd65d
parent 050fdfe9840c3fa5439f1ad8064c52f72c9c79f9
author Takuto Ikuta <tikuta@google.com> 1518126760 +0900
committer Qijiang Fan <fqj@google.com> 1591313349 +0900

Do not update file timestamp if file content is not updated in mojom generators

Timestamp of file should not be updated if there is already the file having the same content.
This CL reduces the number of compile tasks in incremental build.

After building all target with linux_chromium_rel_ng builder config, I touched files in this change and see the number of incremental compile tasks when I rebuild all target.
Without this CL: 25158
With this CL: 7098

This CL reduces at most around 18000 compile tasks in incremental build.

Bug: 810298
Change-Id: Ie7f465dd935b6ae5ee901906a25acea741d42530
Reviewed-on: https://chromium-review.googlesource.com/908268
Reviewed-by: Ken Rockot <rockot@chromium.org>
Commit-Queue: Takuto Ikuta <tikuta@google.com>
Cr-Commit-Position: refs/heads/master@{#535533}

CrOS-Libchrome-Original-Commit: 2a4bf9de46bf71de74e22ffc73bcfa681d67cae8