A zillion classes do this, so I'm repurposing this bug.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/501900f5a00aec0af5b5e9ed62ae933aead7fffa

commit 501900f5a00aec0af5b5e9ed62ae933aead7fffa
Author: derat <derat@chromium.org>
Date: Wed Aug 10 23:52:36 2016

chromeos: Don't spam logs with update_engine D-Bus errors.

Make UpdateEngineClientImpl wait to get update_engine's
initial status until D-Bus has notified us that it's
available.

BUG= 636554 

Review-Url: https://codereview.chromium.org/2239513002
Cr-Commit-Position: refs/heads/master@{#411190}

[modify] https://crrev.com/501900f5a00aec0af5b5e9ed62ae933aead7fffa/chromeos/dbus/update_engine_client.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/08c5efaa7689e8a51c780ec117adaed7cd035842

commit 08c5efaa7689e8a51c780ec117adaed7cd035842
Author: derat <derat@chromium.org>
Date: Thu Aug 11 03:18:37 2016

chromeos: Update update_engine D-Bus availability code.

Rename a method in UpdateEngineClient and add an error
message to reflect the way that
dbus::ObjectProxy::WaitForServiceToBeAvailable() actually
works.

BUG= 636554 
TBR=stevenjb@chromium.org

Review-Url: https://codereview.chromium.org/2238763002
Cr-Commit-Position: refs/heads/master@{#411247}

[modify] https://crrev.com/08c5efaa7689e8a51c780ec117adaed7cd035842/chromeos/dbus/update_engine_client.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/709228f565b22a2115bdbbac2f6b804055699d07

commit 709228f565b22a2115bdbbac2f6b804055699d07
Author: derat <derat@chromium.org>
Date: Thu Aug 11 17:29:23 2016

chromeos: Don't spam logs with tlsdate D-Bus errors at boot.

Make SystemClockClientImpl avoid making its initial call to
tlsdate to check if the time can be set until D-Bus has
notified it that tlsdate is available.

BUG= 636554 

Review-Url: https://codereview.chromium.org/2236713002
Cr-Commit-Position: refs/heads/master@{#411369}

[modify] https://crrev.com/709228f565b22a2115bdbbac2f6b804055699d07/chromeos/dbus/system_clock_client.cc
[modify] https://crrev.com/709228f565b22a2115bdbbac2f6b804055699d07/chromeos/dbus/system_clock_client.h

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/66e73f0329fbc2953bcc65d07d548a00441e625c

commit 66e73f0329fbc2953bcc65d07d548a00441e625c
Author: derat <derat@chromium.org>
Date: Tue Aug 23 15:45:17 2016

chromeos: Avoid org.neard.Manager D-Bus log spam.

Make NfcManagerClientImpl defer making its initial call to
get neard's properties until D-Bus has notified Chrome that
neard is available.

BUG= 636554 
TBR=stevenjb@chromium.org

Review-Url: https://codereview.chromium.org/2238703002
Cr-Commit-Position: refs/heads/master@{#413743}

[modify] https://crrev.com/66e73f0329fbc2953bcc65d07d548a00441e625c/chromeos/dbus/nfc_client_unittest.cc
[modify] https://crrev.com/66e73f0329fbc2953bcc65d07d548a00441e625c/chromeos/dbus/nfc_manager_client.cc
[modify] https://crrev.com/66e73f0329fbc2953bcc65d07d548a00441e625c/dbus/mock_object_proxy.h

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/2ef7d0eda3fe8cb8a73c3ce977b8f1768cd32ece

commit 2ef7d0eda3fe8cb8a73c3ce977b8f1768cd32ece
Author: derat <derat@chromium.org>
Date: Thu Sep 08 21:35:51 2016

dbus: Make ObjectManager get objects after service is ready.

Make dbus::ObjectManager automatically fetch managed objects
after the remote service becomes available. Also remove
Bus::GetManagedObjects(), which produces a large amount of
log spam due to some services not yet being ready. (It was
called by chromeos::DBusThreadManager and
bluez::BluezDBusManager at startup.)

BUG= 636554 

Review-Url: https://codereview.chromium.org/2239123002
Cr-Commit-Position: refs/heads/master@{#417405}

[modify] https://crrev.com/2ef7d0eda3fe8cb8a73c3ce977b8f1768cd32ece/chromeos/dbus/dbus_thread_manager.cc
[modify] https://crrev.com/2ef7d0eda3fe8cb8a73c3ce977b8f1768cd32ece/dbus/bus.cc
[modify] https://crrev.com/2ef7d0eda3fe8cb8a73c3ce977b8f1768cd32ece/dbus/bus.h
[modify] https://crrev.com/2ef7d0eda3fe8cb8a73c3ce977b8f1768cd32ece/dbus/mock_object_manager.h
[modify] https://crrev.com/2ef7d0eda3fe8cb8a73c3ce977b8f1768cd32ece/dbus/object_manager.cc
[modify] https://crrev.com/2ef7d0eda3fe8cb8a73c3ce977b8f1768cd32ece/dbus/object_manager.h
[modify] https://crrev.com/2ef7d0eda3fe8cb8a73c3ce977b8f1768cd32ece/device/bluetooth/dbus/bluez_dbus_manager.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/8f07351eab26e3b2d49fd4aa3c81f19e9656d6c2

commit 8f07351eab26e3b2d49fd4aa3c81f19e9656d6c2
Author: derat <derat@chromium.org>
Date: Fri Sep 16 16:06:43 2016

chromeos: Avoid cryptohome D-Bus log spam at boot.

Make EnterpriseInstallAttributes defer running its
consistency check (which calls cryptohome's TpmIsOwned
method over D-Bus) until the cryptohome service is
available.

Also fix an apparent bug where the check was retried five
times the intended number of times.

BUG= 636554 

Review-Url: https://codereview.chromium.org/2244443002
Cr-Commit-Position: refs/heads/master@{#419180}

[modify] https://crrev.com/8f07351eab26e3b2d49fd4aa3c81f19e9656d6c2/chrome/browser/chromeos/policy/enterprise_install_attributes.cc
[modify] https://crrev.com/8f07351eab26e3b2d49fd4aa3c81f19e9656d6c2/chrome/browser/chromeos/policy/enterprise_install_attributes.h

I think that all of these messages are gone now!

I take that back; there's still some repeated cryptohome spam related to easy unlock:

[1912:1912:0916/102203:ERROR:object_proxy.cc(583)] Failed to call method: org.chromium.CryptohomeInterface.GetKeyDataEx: object_path= /org/chromium/Cryptohome: org.freedesktop.DBus.Error.ServiceUnknown: The name org.chromium.Cryptohome was not provided by any .service files
[1912:1912:0916/102203:ERROR:easy_unlock_get_keys_operation.cc(61)] Easy unlock failed to get key data, code=1

I see this repeated four times when booting a samus device.

It is probably from attempting to ready easy unlock key data on the focused user before cryptohomed is ready.

Think the call stack is roughly:
focused user pod change (on start, tab or click on a pod) ->
EasyUnlockServiceSignin::LoadCurrentUserDataIfNeeded ->
LoadDataForUser ->
EasyUnlockKeyManager::GetDeviceDataList ->
EasyUnlockGetKeysOperation::GetKeyData ->
calls cryptohome GetKeyDataEx

We probably can add a cryptohome service ready wait somewhere in the stack.

Thanks, looks like it.

Using WaitForServiceToBeAvailable() will speed this up since we'll call the service as soon as it's available instead of waiting longer than necessary for a retry delay.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/e704807ee8bdb5829fb147f59b74e3a218f4de04

commit e704807ee8bdb5829fb147f59b74e3a218f4de04
Author: derat <derat@chromium.org>
Date: Fri Sep 16 18:38:40 2016

chromeos: Avoid EasyUnlockGetKeysOperation D-Bus log spam.

Make EasyUnlockGetKeysOperation wait for the cryptohome
D-Bus service to be available before making a GetKeyDataEx
method call to it. Otherwise, we get repeated log spam at
boot:

  [1912:1912:0916/102203:ERROR:object_proxy.cc(583)] Failed to call method: org.chromium.CryptohomeInterface.GetKeyDataEx: object_path= /org/chromium/Cryptohome: org.freedesktop.DBus.Error.ServiceUnknown: The name org.chromium.Cryptohome was not provided by any .service files
  [1912:1912:0916/102203:ERROR:easy_unlock_get_keys_operation.cc(61)] Easy unlock failed to get key data, code=1

BUG= 636554 

Review-Url: https://codereview.chromium.org/2343213002
Cr-Commit-Position: refs/heads/master@{#419228}

[modify] https://crrev.com/e704807ee8bdb5829fb147f59b74e3a218f4de04/chrome/browser/chromeos/login/easy_unlock/easy_unlock_get_keys_operation.cc
[modify] https://crrev.com/e704807ee8bdb5829fb147f59b74e3a218f4de04/chrome/browser/chromeos/login/easy_unlock/easy_unlock_get_keys_operation.h