The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/df000848b18809fa5dbcf0cd5e45da6a7f1e673a

commit df000848b18809fa5dbcf0cd5e45da6a7f1e673a
Author: timvolodine <timvolodine@chromium.org>
Date: Thu Nov 03 20:34:32 2016

[Android] spellcheck: add latency UMA.

Add spellchecking service latency measurement on Android.
This measures how long it takes for the spellchecker to
return results. The purpose is to understand performance
characteristics of spellchecking on various devices.

Also during testing we have encountered some slow response
times on Nexus 5 Android Lollipop device, which however were
resolved after updating the "Google Keyboard" app via Google
Play. This UMA will help us understand if there are any such
regressions in the field and how frequent they are.

BUG=660074, 629609

Review-Url: https://codereview.chromium.org/2457873002
Cr-Commit-Position: refs/heads/master@{#429687}

[modify] https://crrev.com/df000848b18809fa5dbcf0cd5e45da6a7f1e673a/components/spellcheck/browser/android/java/src/org/chromium/components/spellcheck/SpellCheckerSessionBridge.java
[modify] https://crrev.com/df000848b18809fa5dbcf0cd5e45da6a7f1e673a/tools/metrics/histograms/histograms.xml

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/d88cfcd00c078a5e54266f1f5f3eda07582f367f

commit d88cfcd00c078a5e54266f1f5f3eda07582f367f
Author: timvolodine <timvolodine@chromium.org>
Date: Thu Nov 17 21:46:00 2016

[Android] spellcheck: add availability UMA.

Add spellchecking service availability measurement on
Android. This measures whether the system spellchecking
service was available at the start of each new
spellchecking session during the editing of textual
input html elements.

Note that the service can be unavailable because the
user has disabled it in the Android settings.

BUG=660074, 629609

Review-Url: https://codereview.chromium.org/2503933002
Cr-Commit-Position: refs/heads/master@{#432975}

[modify] https://crrev.com/d88cfcd00c078a5e54266f1f5f3eda07582f367f/components/spellcheck/browser/spellchecker_session_bridge_android.cc
[modify] https://crrev.com/d88cfcd00c078a5e54266f1f5f3eda07582f367f/components/spellcheck/browser/spellchecker_session_bridge_android.h
[modify] https://crrev.com/d88cfcd00c078a5e54266f1f5f3eda07582f367f/tools/metrics/histograms/histograms.xml