Removing this from the security queue since there's no concrete vulnerability here.

Hi

I just found these two static functions (base::Time::FromString and base::Time::FromUTCString) need be tagged as WARN_UNUSED_RESULT.

Are there any missing functions?

Thanks

https://codereview.chromium.org/2605293002/

On that CL: It looks like > 20% of callers of FromString don't care about the result of these functions (the CL just adds ignore_result there). That seems too high for WARN_UNUSED_RESULT; that should only be used if not checking the result of a function is a clear bug. (Else we'd just add it to every function returning a value.)

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/2c8eed34518aa37ebe2decc78af0694e1826c43b

commit 2c8eed34518aa37ebe2decc78af0694e1826c43b
Author: digit <digit@chromium.org>
Date: Thu Jan 12 20:49:41 2017

Add WARN_UNUSED_RESULT to base::Time methods that return bool.

base::Time::FromString() and base::Time::FromUTCString() might fail
at runtime on bad input. This adds a WARN_UNUSED_RESULT to their
declarations to ensure that all callers properly handle the result.

Apart from unit-tests, this changes two things:

- DataUseTracker::RemoveExpiredEntriesForPref() will also
  remove any entries with an invalid date string.

  This doesn't change the runtime behaviour though, because
  a failure in base::Time::FromUTCString() would keep the
  local |key_date| variable to 0, which would have been
  considered too old anyway.

- VariationsSeedStore::ImportFirstRunJavaSeed() has
  a new failure mode triggered by an invalid response
  date |FIRST_RUN_SEED_IMPORT_FAIL_INVALID_RESPONSE_DATE|

  It looks like the FirstRunResult enum values are only
  used on Android to report UMA metrics, so ensure that
  the new constant is added at the end of the list to
  avoid generating confusing histograms.

- PexeDownloader::didReceiveResponse() still ignores
  invalid HTTP response 'last-modified' header dates.
  As with RemoveExpiredEntriesForPref() this doesn't
  change the runtime behaviour, but it is hard to see
  whether this is desirable or dangerous.

- ConvertRequestValueToFileInfo() still ignores
  invalid date strings, as mentioned by the comment
  above the base::Time::FromString() line.

BUG= 669625 

Review-Url: https://codereview.chromium.org/2605293002
Cr-Commit-Position: refs/heads/master@{#443353}

[modify] https://crrev.com/2c8eed34518aa37ebe2decc78af0694e1826c43b/base/time/time.h
[modify] https://crrev.com/2c8eed34518aa37ebe2decc78af0694e1826c43b/chrome/browser/chromeos/file_system_provider/operations/get_metadata.cc
[modify] https://crrev.com/2c8eed34518aa37ebe2decc78af0694e1826c43b/chrome/browser/chromeos/mobile_config_unittest.cc
[modify] https://crrev.com/2c8eed34518aa37ebe2decc78af0694e1826c43b/components/data_reduction_proxy/core/browser/data_reduction_proxy_compression_stats_unittest.cc
[modify] https://crrev.com/2c8eed34518aa37ebe2decc78af0694e1826c43b/components/metrics/data_use_tracker.cc
[modify] https://crrev.com/2c8eed34518aa37ebe2decc78af0694e1826c43b/components/metrics/data_use_tracker_unittest.cc
[modify] https://crrev.com/2c8eed34518aa37ebe2decc78af0694e1826c43b/components/nacl/browser/pnacl_translation_cache_unittest.cc
[modify] https://crrev.com/2c8eed34518aa37ebe2decc78af0694e1826c43b/components/nacl/renderer/ppb_nacl_private_impl.cc
[modify] https://crrev.com/2c8eed34518aa37ebe2decc78af0694e1826c43b/components/variations/variations_seed_store.cc
[modify] https://crrev.com/2c8eed34518aa37ebe2decc78af0694e1826c43b/content/browser/blob_storage/blob_storage_context_unittest.cc
[modify] https://crrev.com/2c8eed34518aa37ebe2decc78af0694e1826c43b/content/browser/loader/upload_data_stream_builder_unittest.cc
[modify] https://crrev.com/2c8eed34518aa37ebe2decc78af0694e1826c43b/net/http/http_response_headers_unittest.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/0e2de9dbb7a8507438b24f2a70be000ccb7a8265

commit 0e2de9dbb7a8507438b24f2a70be000ccb7a8265
Author: digit <digit@chromium.org>
Date: Fri Jan 20 14:40:32 2017

histograms.xml: Add missing new value for FirstRunResult.

This is a follow-up to https://codereview.chromium.org/2605293002/
which introduced a new enum value in the Variations.FirstRunResult
historgram to account for seed import failure, in the case of an
invalid response date string.

BUG= 669625 
R=asvitkine@chromium.org

Review-Url: https://codereview.chromium.org/2646743003
Cr-Commit-Position: refs/heads/master@{#445051}

[modify] https://crrev.com/0e2de9dbb7a8507438b24f2a70be000ccb7a8265/tools/metrics/histograms/histograms.xml