[Contextual Search] Add metrics to track Taps before Open.

[Contextual Search] Add metrics to track Taps before Open.

Adds several new histograms for Contextual Search to track:
The total number of taps before ever opening the promo panel,
the number of times the promo panel was opened, the number
of taps since any panel was opened, and information about the
search term resolution (protocol, and single/multi-word).

There's a downstream CL dependent on this change: https://chrome-internal-review.googlesource.com/#/c/216388/

BUG=477827
Committed: https://crrev.com/3f5bbf5e784ae8d79708c4bb5f554c3a21dc9b13
Cr-Commit-Position: refs/heads/master@{#330841}

[Donn Denman, 2015-05-14 21:51:34]

donnd@chromium.org changed reviewers:
+ pedrosimonetti@chromium.org, twellington@chromium.org

[Donn Denman, 2015-05-14 21:53:46]

Pedro and Theresa (and Aurimas if you feel inclined): Please take a look at this
CL which defines the new histograms I'd like to add.  I'll send out the
downstream CL that uses these shortly.  Also the update the the histograms.xml
will be done after all the chrome commits land.

Please double-check that the names seem reasonable, since they will guide the
user-readable values that we'll put into histograms.xml.

Thanks!

[Theresa, 2015-05-15 16:32:39]

https://chromiumcodereview.appspot.com/1131653005/diff/1/chrome/android/java/...
File
chrome/android/java/src/org/chromium/chrome/browser/contextualsearch/ContextualSearchUma.java
(right):

https://chromiumcodereview.appspot.com/1131653005/diff/1/chrome/android/java/...
chrome/android/java/src/org/chromium/chrome/browser/contextualsearch/ContextualSearchUma.java:427:
@Deprecated
Should the @Deprecated label be moved about the zero-parameter version of
logPreferenceState()? Or dropped entirely? It looks like the zero-param version
still has use in the downstream CL.

Also, since this method calls logPromoTapsReamining, should this method only be
called for users that are still undecided?

[Donn Denman, 2015-05-16 01:26:52]

Thanks Teresa!

Pedro, PTAL no sooner than Monday!

https://chromiumcodereview.appspot.com/1131653005/diff/1/chrome/android/java/...
File
chrome/android/java/src/org/chromium/chrome/browser/contextualsearch/ContextualSearchUma.java
(right):

https://chromiumcodereview.appspot.com/1131653005/diff/1/chrome/android/java/...
chrome/android/java/src/org/chromium/chrome/browser/contextualsearch/ContextualSearchUma.java:427:
@Deprecated
On 2015/05/15 16:32:39, Theresa Wellington wrote:
> Should the @Deprecated label be moved about the zero-parameter version of
> logPreferenceState()? Or dropped entirely? It looks like the zero-param
version
> still has use in the downstream CL.
> 
> Also, since this method calls logPromoTapsReamining, should this method only
be
> called for users that are still undecided?

Nice catch -- this isn't right.  The version with one parameter that I'm
deprecating should just behave the same way it always did (since it's just there
for compatibility until the downstream code lands).

I keep changing my mind about whether to pass the parameter and do extra logging
for that parameter.  My latest thinking is that these methods should be as
simple as possible, and just log one thing, not multiple things.  So I'm
deprecating the one with the parameter and splitting it in two.

I noticed that I changed the order of the two methods, so I'll change that back.

Does this all make sense now?

[Donn Denman, 2015-05-16 01:28:37]

err, meant Theresa.

[pedro (no code reviews), 2015-05-20 19:13:21]

lgtm

[Theresa, 2015-05-20 19:18:38]

lgtm too :)

[Donn Denman, 2015-05-20 20:32:39]

donnd@chromium.org changed reviewers:
+ mariakhomenko@chromium.org

[Donn Denman, 2015-05-20 20:32:40]

Maria, PTAL at these metrics we're planning to add to CS.  Thanks!

[Maria, 2015-05-20 22:16:11]

lgtm

[Donn Denman, 2015-05-20 22:40:44]

The CQ bit was checked by donnd@chromium.org

[Donn Denman, 2015-05-20 22:40:45]

The patchset sent to the CQ was uploaded after l-g-t-m from
twellington@chromium.org, pedrosimonetti@chromium.org
Link to the patchset: https://chromiumcodereview.appspot.com/1131653005/#ps60001
(title: "rebase")

[commit-bot: I haz the power, 2015-05-20 22:42:02]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1131653005/60001

[commit-bot: I haz the power, 2015-05-20 23:34:04]

Committed patchset #4 (id:60001)

[commit-bot: I haz the power, 2015-05-20 23:35:49]

Patchset 4 (id:??) landed as
https://crrev.com/3f5bbf5e784ae8d79708c4bb5f554c3a21dc9b13
Cr-Commit-Position: refs/heads/master@{#330841}