[GN] Don't rewrite files with the same contents

[GN] Don't rewrite files with the same contents

Reland of https://codereview.chromium.org/1656253003 with fix.

Reason for revert:
Need to revert this patch according https://sites.google.com/a/chromium.org/dev/developers/tree-sheriffs/sheriffing-bug-queues. This patch added a flaky test FilesystemUtils.WriteFileIfChanged.

-----

It's a test flake:
1) Try to find the patch that caused the flake. It should be recent (e.g. last day or two) in all likelihood.
2) If successful with finding that patch, revert the patch. This is especially true if the flake is from a new test introduced in that patch.
3) Close the bug.

-----

The test has failed in the following builds:

http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_rel_ng/builds/176911
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_rel_ng/builds/176911
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_rel_ng/builds/176735
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_rel_ng/builds/176715
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_rel_ng/builds/176715
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_rel_ng/builds/176561
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_rel_ng/builds/176462
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_rel_ng/builds/176375

-----

Example failure:

[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04 18:06:36.920 UTC vs 2016-02-04 18:06:36.920 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (3 ms)
[315/315] FilesystemUtils.WriteFileIfChanged (3 ms)
Retrying 1 test (retry #2)
[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04 18:06:36.936 UTC vs 2016-02-04 18:06:36.936 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (2 ms)
[316/316] FilesystemUtils.WriteFileIfChanged (2 ms)
Retrying 1 test (retry #3)
[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04 18:06:36.952 UTC vs 2016-02-04 18:06:36.952 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (2 ms)
[317/317] FilesystemUtils.WriteFileIfChanged (2 ms)
1 test failed:
    FilesystemUtils.WriteFileIfChanged (../../tools/gn/filesystem_utils_unittest.cc:579)

-----

More details in http://crbug.com/584548.

Original issue's description:
> [GN] Don't rewrite files with the same contents
>
> BUG=
>
> Committed: https://crrev.com/f8ea5cceefcedd4a01935d5ac4d2ba71e23ac13e
> Cr-Commit-Position: refs/heads/master@{#373544}

BUG=584548
Committed: https://crrev.com/36deb395534c77295db41cc5f3e6b9627fbc5aa8
Cr-Commit-Position: refs/heads/master@{#376430}

[Tomasz Moniuszko, 2016-02-18 15:24:47]

Description was changed from

==========
[GN] Don't rewrite files with the same contents

BUG=
==========

to

==========
Reland of [GN] Don't rewrite files with the same contents

(patchset #5 id:80001 of https://codereview.chromium.org/1656253003/ )

Reason for revert:
Need to revert this patch according
https://sites.google.com/a/chromium.org/dev/developers/tree-sheriffs/sheriffi....
This patch added a flaky test FilesystemUtils.WriteFileIfChanged.

-----

It's a test flake:
1) Try to find the patch that caused the flake. It should be recent (e.g. last
day or two) in all likelihood.
2) If successful with finding that patch, revert the patch. This is especially
true if the flake is from a new test introduced in that patch.
3) Close the bug.

-----

The test has failed in the following builds:

http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...

-----

Example failure:

[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04
18:06:36.920 UTC vs 2016-02-04 18:06:36.920 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (3 ms)
[315/315] FilesystemUtils.WriteFileIfChanged (3 ms)
Retrying 1 test (retry #2)
[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04
18:06:36.936 UTC vs 2016-02-04 18:06:36.936 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (2 ms)
[316/316] FilesystemUtils.WriteFileIfChanged (2 ms)
Retrying 1 test (retry #3)
[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04
18:06:36.952 UTC vs 2016-02-04 18:06:36.952 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (2 ms)
[317/317] FilesystemUtils.WriteFileIfChanged (2 ms)
1 test failed:
    FilesystemUtils.WriteFileIfChanged
(../../tools/gn/filesystem_utils_unittest.cc:579)

-----

More details in http://crbug.com/584548.

Original issue's description:
> [GN] Don't rewrite files with the same contents
>
> BUG=
>
> Committed: https://crrev.com/f8ea5cceefcedd4a01935d5ac4d2ba71e23ac13e
> Cr-Commit-Position: refs/heads/master@{#373544}
==========

[Tomasz Moniuszko, 2016-02-18 15:24:48]

tmoniuszko@opera.com changed reviewers:
+ brettw@chromium.org

[Tomasz Moniuszko, 2016-02-18 15:27:29]

FilesystemUtils.WriteFileIfChanged test fixed. Now it compares file contents
instead of modification time in case when new contents is written.

[Tomasz Moniuszko, 2016-02-18 15:30:02]

Description was changed from

==========
Reland of [GN] Don't rewrite files with the same contents

(patchset #5 id:80001 of https://codereview.chromium.org/1656253003/ )

Reason for revert:
Need to revert this patch according
https://sites.google.com/a/chromium.org/dev/developers/tree-sheriffs/sheriffi....
This patch added a flaky test FilesystemUtils.WriteFileIfChanged.

-----

It's a test flake:
1) Try to find the patch that caused the flake. It should be recent (e.g. last
day or two) in all likelihood.
2) If successful with finding that patch, revert the patch. This is especially
true if the flake is from a new test introduced in that patch.
3) Close the bug.

-----

The test has failed in the following builds:

http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...

-----

Example failure:

[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04
18:06:36.920 UTC vs 2016-02-04 18:06:36.920 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (3 ms)
[315/315] FilesystemUtils.WriteFileIfChanged (3 ms)
Retrying 1 test (retry #2)
[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04
18:06:36.936 UTC vs 2016-02-04 18:06:36.936 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (2 ms)
[316/316] FilesystemUtils.WriteFileIfChanged (2 ms)
Retrying 1 test (retry #3)
[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04
18:06:36.952 UTC vs 2016-02-04 18:06:36.952 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (2 ms)
[317/317] FilesystemUtils.WriteFileIfChanged (2 ms)
1 test failed:
    FilesystemUtils.WriteFileIfChanged
(../../tools/gn/filesystem_utils_unittest.cc:579)

-----

More details in http://crbug.com/584548.

Original issue's description:
> [GN] Don't rewrite files with the same contents
>
> BUG=
>
> Committed: https://crrev.com/f8ea5cceefcedd4a01935d5ac4d2ba71e23ac13e
> Cr-Commit-Position: refs/heads/master@{#373544}
==========

to

==========
Reland of [GN] Don't rewrite files with the same contents

(patchset #5 id:80001 of https://codereview.chromium.org/1656253003/ )

Reason for revert:
Need to revert this patch according
https://sites.google.com/a/chromium.org/dev/developers/tree-sheriffs/sheriffi....
This patch added a flaky test FilesystemUtils.WriteFileIfChanged.

-----

It's a test flake:
1) Try to find the patch that caused the flake. It should be recent (e.g. last
day or two) in all likelihood.
2) If successful with finding that patch, revert the patch. This is especially
true if the flake is from a new test introduced in that patch.
3) Close the bug.

-----

The test has failed in the following builds:

http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...

-----

Example failure:

[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04
18:06:36.920 UTC vs 2016-02-04 18:06:36.920 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (3 ms)
[315/315] FilesystemUtils.WriteFileIfChanged (3 ms)
Retrying 1 test (retry #2)
[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04
18:06:36.936 UTC vs 2016-02-04 18:06:36.936 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (2 ms)
[316/316] FilesystemUtils.WriteFileIfChanged (2 ms)
Retrying 1 test (retry #3)
[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04
18:06:36.952 UTC vs 2016-02-04 18:06:36.952 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (2 ms)
[317/317] FilesystemUtils.WriteFileIfChanged (2 ms)
1 test failed:
    FilesystemUtils.WriteFileIfChanged
(../../tools/gn/filesystem_utils_unittest.cc:579)

-----

More details in http://crbug.com/584548.

Original issue's description:
> [GN] Don't rewrite files with the same contents
>
> BUG=
>
> Committed: https://crrev.com/f8ea5cceefcedd4a01935d5ac4d2ba71e23ac13e
> Cr-Commit-Position: refs/heads/master@{#373544}

BUG=584548
==========

[brettw, 2016-02-18 21:43:55]

lgtm

LGTM, can you clean up the commit message? I normally use the original commit
message and say "reland of http://codereview.... with fix"

I usually try to remember to upload first an unmodified revert, then the fix as
a 2nd patch so it's easier for the reviewer to see the diff.

[Tomasz Moniuszko, 2016-02-19 10:43:34]

Description was changed from

==========
Reland of [GN] Don't rewrite files with the same contents

(patchset #5 id:80001 of https://codereview.chromium.org/1656253003/ )

Reason for revert:
Need to revert this patch according
https://sites.google.com/a/chromium.org/dev/developers/tree-sheriffs/sheriffi....
This patch added a flaky test FilesystemUtils.WriteFileIfChanged.

-----

It's a test flake:
1) Try to find the patch that caused the flake. It should be recent (e.g. last
day or two) in all likelihood.
2) If successful with finding that patch, revert the patch. This is especially
true if the flake is from a new test introduced in that patch.
3) Close the bug.

-----

The test has failed in the following builds:

http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...

-----

Example failure:

[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04
18:06:36.920 UTC vs 2016-02-04 18:06:36.920 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (3 ms)
[315/315] FilesystemUtils.WriteFileIfChanged (3 ms)
Retrying 1 test (retry #2)
[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04
18:06:36.936 UTC vs 2016-02-04 18:06:36.936 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (2 ms)
[316/316] FilesystemUtils.WriteFileIfChanged (2 ms)
Retrying 1 test (retry #3)
[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04
18:06:36.952 UTC vs 2016-02-04 18:06:36.952 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (2 ms)
[317/317] FilesystemUtils.WriteFileIfChanged (2 ms)
1 test failed:
    FilesystemUtils.WriteFileIfChanged
(../../tools/gn/filesystem_utils_unittest.cc:579)

-----

More details in http://crbug.com/584548.

Original issue's description:
> [GN] Don't rewrite files with the same contents
>
> BUG=
>
> Committed: https://crrev.com/f8ea5cceefcedd4a01935d5ac4d2ba71e23ac13e
> Cr-Commit-Position: refs/heads/master@{#373544}

BUG=584548
==========

to

==========
[GN] Don't rewrite files with the same contents

Reland of https://codereview.chromium.org/1656253003 with fix.

Reason for revert:
Need to revert this patch according
https://sites.google.com/a/chromium.org/dev/developers/tree-sheriffs/sheriffi....
This patch added a flaky test FilesystemUtils.WriteFileIfChanged.

-----

It's a test flake:
1) Try to find the patch that caused the flake. It should be recent (e.g. last
day or two) in all likelihood.
2) If successful with finding that patch, revert the patch. This is especially
true if the flake is from a new test introduced in that patch.
3) Close the bug.

-----

The test has failed in the following builds:

http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...

-----

Example failure:

[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04
18:06:36.920 UTC vs 2016-02-04 18:06:36.920 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (3 ms)
[315/315] FilesystemUtils.WriteFileIfChanged (3 ms)
Retrying 1 test (retry #2)
[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04
18:06:36.936 UTC vs 2016-02-04 18:06:36.936 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (2 ms)
[316/316] FilesystemUtils.WriteFileIfChanged (2 ms)
Retrying 1 test (retry #3)
[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04
18:06:36.952 UTC vs 2016-02-04 18:06:36.952 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (2 ms)
[317/317] FilesystemUtils.WriteFileIfChanged (2 ms)
1 test failed:
    FilesystemUtils.WriteFileIfChanged
(../../tools/gn/filesystem_utils_unittest.cc:579)

-----

More details in http://crbug.com/584548.

Original issue's description:
> [GN] Don't rewrite files with the same contents
>
> BUG=
>
> Committed: https://crrev.com/f8ea5cceefcedd4a01935d5ac4d2ba71e23ac13e
> Cr-Commit-Position: refs/heads/master@{#373544}

BUG=584548
==========

[Tomasz Moniuszko, 2016-02-19 10:43:52]

The CQ bit was checked by tmoniuszko@opera.com

[Tomasz Moniuszko, 2016-02-19 10:45:34]

On 2016/02/18 21:43:55, brettw wrote:
> lgtm
> 
> LGTM, can you clean up the commit message? I normally use the original commit
> message and say "reland of http://codereview.... with fix"

Done.

> 
> I usually try to remember to upload first an unmodified revert, then the fix
as
> a 2nd patch so it's easier for the reviewer to see the diff.

OK. I will remember to do this next time.

[commit-bot: I haz the power, 2016-02-19 10:46:02]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1704383002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1704383002/1

[commit-bot: I haz the power, 2016-02-19 11:16:49]

Description was changed from

==========
[GN] Don't rewrite files with the same contents

Reland of https://codereview.chromium.org/1656253003 with fix.

Reason for revert:
Need to revert this patch according
https://sites.google.com/a/chromium.org/dev/developers/tree-sheriffs/sheriffi....
This patch added a flaky test FilesystemUtils.WriteFileIfChanged.

-----

It's a test flake:
1) Try to find the patch that caused the flake. It should be recent (e.g. last
day or two) in all likelihood.
2) If successful with finding that patch, revert the patch. This is especially
true if the flake is from a new test introduced in that patch.
3) Close the bug.

-----

The test has failed in the following builds:

http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...

-----

Example failure:

[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04
18:06:36.920 UTC vs 2016-02-04 18:06:36.920 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (3 ms)
[315/315] FilesystemUtils.WriteFileIfChanged (3 ms)
Retrying 1 test (retry #2)
[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04
18:06:36.936 UTC vs 2016-02-04 18:06:36.936 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (2 ms)
[316/316] FilesystemUtils.WriteFileIfChanged (2 ms)
Retrying 1 test (retry #3)
[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04
18:06:36.952 UTC vs 2016-02-04 18:06:36.952 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (2 ms)
[317/317] FilesystemUtils.WriteFileIfChanged (2 ms)
1 test failed:
    FilesystemUtils.WriteFileIfChanged
(../../tools/gn/filesystem_utils_unittest.cc:579)

-----

More details in http://crbug.com/584548.

Original issue's description:
> [GN] Don't rewrite files with the same contents
>
> BUG=
>
> Committed: https://crrev.com/f8ea5cceefcedd4a01935d5ac4d2ba71e23ac13e
> Cr-Commit-Position: refs/heads/master@{#373544}

BUG=584548
==========

to

==========
[GN] Don't rewrite files with the same contents

Reland of https://codereview.chromium.org/1656253003 with fix.

Reason for revert:
Need to revert this patch according
https://sites.google.com/a/chromium.org/dev/developers/tree-sheriffs/sheriffi....
This patch added a flaky test FilesystemUtils.WriteFileIfChanged.

-----

It's a test flake:
1) Try to find the patch that caused the flake. It should be recent (e.g. last
day or two) in all likelihood.
2) If successful with finding that patch, revert the patch. This is especially
true if the flake is from a new test introduced in that patch.
3) Close the bug.

-----

The test has failed in the following builds:

http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...

-----

Example failure:

[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04
18:06:36.920 UTC vs 2016-02-04 18:06:36.920 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (3 ms)
[315/315] FilesystemUtils.WriteFileIfChanged (3 ms)
Retrying 1 test (retry #2)
[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04
18:06:36.936 UTC vs 2016-02-04 18:06:36.936 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (2 ms)
[316/316] FilesystemUtils.WriteFileIfChanged (2 ms)
Retrying 1 test (retry #3)
[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04
18:06:36.952 UTC vs 2016-02-04 18:06:36.952 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (2 ms)
[317/317] FilesystemUtils.WriteFileIfChanged (2 ms)
1 test failed:
    FilesystemUtils.WriteFileIfChanged
(../../tools/gn/filesystem_utils_unittest.cc:579)

-----

More details in http://crbug.com/584548.

Original issue's description:
> [GN] Don't rewrite files with the same contents
>
> BUG=
>
> Committed: https://crrev.com/f8ea5cceefcedd4a01935d5ac4d2ba71e23ac13e
> Cr-Commit-Position: refs/heads/master@{#373544}

BUG=584548
==========

[commit-bot: I haz the power, 2016-02-19 11:16:50]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-02-19 11:17:58]

Description was changed from

==========
[GN] Don't rewrite files with the same contents

Reland of https://codereview.chromium.org/1656253003 with fix.

Reason for revert:
Need to revert this patch according
https://sites.google.com/a/chromium.org/dev/developers/tree-sheriffs/sheriffi....
This patch added a flaky test FilesystemUtils.WriteFileIfChanged.

-----

It's a test flake:
1) Try to find the patch that caused the flake. It should be recent (e.g. last
day or two) in all likelihood.
2) If successful with finding that patch, revert the patch. This is especially
true if the flake is from a new test introduced in that patch.
3) Close the bug.

-----

The test has failed in the following builds:

http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...

-----

Example failure:

[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04
18:06:36.920 UTC vs 2016-02-04 18:06:36.920 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (3 ms)
[315/315] FilesystemUtils.WriteFileIfChanged (3 ms)
Retrying 1 test (retry #2)
[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04
18:06:36.936 UTC vs 2016-02-04 18:06:36.936 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (2 ms)
[316/316] FilesystemUtils.WriteFileIfChanged (2 ms)
Retrying 1 test (retry #3)
[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04
18:06:36.952 UTC vs 2016-02-04 18:06:36.952 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (2 ms)
[317/317] FilesystemUtils.WriteFileIfChanged (2 ms)
1 test failed:
    FilesystemUtils.WriteFileIfChanged
(../../tools/gn/filesystem_utils_unittest.cc:579)

-----

More details in http://crbug.com/584548.

Original issue's description:
> [GN] Don't rewrite files with the same contents
>
> BUG=
>
> Committed: https://crrev.com/f8ea5cceefcedd4a01935d5ac4d2ba71e23ac13e
> Cr-Commit-Position: refs/heads/master@{#373544}

BUG=584548
==========

to

==========
[GN] Don't rewrite files with the same contents

Reland of https://codereview.chromium.org/1656253003 with fix.

Reason for revert:
Need to revert this patch according
https://sites.google.com/a/chromium.org/dev/developers/tree-sheriffs/sheriffi....
This patch added a flaky test FilesystemUtils.WriteFileIfChanged.

-----

It's a test flake:
1) Try to find the patch that caused the flake. It should be recent (e.g. last
day or two) in all likelihood.
2) If successful with finding that patch, revert the patch. This is especially
true if the flake is from a new test introduced in that patch.
3) Close the bug.

-----

The test has failed in the following builds:

http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...

-----

Example failure:

[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04
18:06:36.920 UTC vs 2016-02-04 18:06:36.920 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (3 ms)
[315/315] FilesystemUtils.WriteFileIfChanged (3 ms)
Retrying 1 test (retry #2)
[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04
18:06:36.936 UTC vs 2016-02-04 18:06:36.936 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (2 ms)
[316/316] FilesystemUtils.WriteFileIfChanged (2 ms)
Retrying 1 test (retry #3)
[ RUN      ] FilesystemUtils.WriteFileIfChanged
../../tools/gn/filesystem_utils_unittest.cc:610: Failure
Expected: (last_modified) != (file_info.last_modified), actual: 2016-02-04
18:06:36.952 UTC vs 2016-02-04 18:06:36.952 UTC
[  FAILED  ] FilesystemUtils.WriteFileIfChanged (2 ms)
[317/317] FilesystemUtils.WriteFileIfChanged (2 ms)
1 test failed:
    FilesystemUtils.WriteFileIfChanged
(../../tools/gn/filesystem_utils_unittest.cc:579)

-----

More details in http://crbug.com/584548.

Original issue's description:
> [GN] Don't rewrite files with the same contents
>
> BUG=
>
> Committed: https://crrev.com/f8ea5cceefcedd4a01935d5ac4d2ba71e23ac13e
> Cr-Commit-Position: refs/heads/master@{#373544}

BUG=584548

Committed: https://crrev.com/36deb395534c77295db41cc5f3e6b9627fbc5aa8
Cr-Commit-Position: refs/heads/master@{#376430}
==========

[commit-bot: I haz the power, 2016-02-19 11:17:59]

Patchset 1 (id:??) landed as
https://crrev.com/36deb395534c77295db41cc5f3e6b9627fbc5aa8
Cr-Commit-Position: refs/heads/master@{#376430}