Add UMA stats for tracking bookmark depth

Add UMA stats for tracking bookmark depth

As part of refreshing bookmarks, we need a better understanding of how hierarchy is used. Adds metrics for depth of bookmarks node not navigated via bookmark manager or omnibox. Also fixes bugs with gtk where any bookmark launches from browser ui but not the bookmark bar (i.e. context menu or hotdogs) aren't recorded 
BUG=312492
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=232600

[Yaron, 2013-11-01 18:35:06]

sky: bookmakrs code
asvitkine: metrics

[sky, 2013-11-01 20:26:37]

https://codereview.chromium.org/49283004/diff/180001/chrome/browser/bookmarks...
File chrome/browser/bookmarks/bookmark_stats.cc (right):

https://codereview.chromium.org/49283004/diff/180001/chrome/browser/bookmarks...
chrome/browser/bookmarks/bookmark_stats.cc:21: if (!node) return;
nit: no single line if.

https://codereview.chromium.org/49283004/diff/180001/chrome/browser/bookmarks...
chrome/browser/bookmarks/bookmark_stats.cc:27: for (const BookmarkNode* iter =
node; !iter->parent()->is_root();
nit: walking up until iter is NULL is less code.

https://codereview.chromium.org/49283004/diff/180001/tools/metrics/histograms...
File tools/metrics/histograms/histograms.xml (right):

https://codereview.chromium.org/49283004/diff/180001/tools/metrics/histograms...
tools/metrics/histograms/histograms.xml:1180: +    bookmark is launched.
You should indicate what the depth corresponds to. By that I mean depth=0
correspond to XXX.

[Yaron, 2013-11-01 22:11:43]

Thanks for the comments

https://codereview.chromium.org/49283004/diff/180001/chrome/browser/bookmarks...
File chrome/browser/bookmarks/bookmark_stats.cc (right):

https://codereview.chromium.org/49283004/diff/180001/chrome/browser/bookmarks...
chrome/browser/bookmarks/bookmark_stats.cc:21: if (!node) return;
On 2013/11/01 20:26:38, sky wrote:
> nit: no single line if.

Done.

https://codereview.chromium.org/49283004/diff/180001/chrome/browser/bookmarks...
chrome/browser/bookmarks/bookmark_stats.cc:27: for (const BookmarkNode* iter =
node; !iter->parent()->is_root();
On 2013/11/01 20:26:38, sky wrote:
> nit: walking up until iter is NULL is less code.

Done.

https://codereview.chromium.org/49283004/diff/180001/tools/metrics/histograms...
File tools/metrics/histograms/histograms.xml (right):

https://codereview.chromium.org/49283004/diff/180001/tools/metrics/histograms...
tools/metrics/histograms/histograms.xml:1180: +    bookmark is launched.
On 2013/11/01 20:26:38, sky wrote:
> You should indicate what the depth corresponds to. By that I mean depth=0
> correspond to XXX.

Done.

[sky, 2013-11-01 22:47:02]

LGTM

[Alexei Svitkine (slow), 2013-11-02 00:06:36]

histograms.xml lgtm

[commit-bot: I haz the power, 2013-11-02 00:42:40]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/yfriedman@chromium.org/49283004/270001

[commit-bot: I haz the power, 2013-11-02 03:44:54]

Retried try job too often on win_rel for step(s) unit_tests
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=win_rel&nu...

[commit-bot: I haz the power, 2013-11-02 08:12:51]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/yfriedman@chromium.org/49283004/270001

[commit-bot: I haz the power, 2013-11-02 13:28:19]

Change committed as 232600