bluetooth: Add histograms and logging for getCharacteristic

bluetooth: Add histograms and logging for getCharacteristic

Histograms:
 - GetCharacteristic.Characteristic: UUID of Characteristic
 - GetCharacteristic.Outcome: Outcome of the call to GetCharacteristic.

BUG=499636
Committed: https://crrev.com/dd0208e1701d7fee6b8104f19bda9a817924c4a3
Cr-Commit-Position: refs/heads/master@{#343451}

[ortuno, 2015-08-12 23:48:15]

Patchset #1 (id:1) has been deleted

[ortuno, 2015-08-12 23:59:39]

Patchset #1 (id:20001) has been deleted

[ortuno, 2015-08-13 00:03:30]

ortuno@chromium.org changed reviewers:
+ jyasskin@chromium.org

[ortuno, 2015-08-13 00:03:30]

@jyasskin: PTAL

[Jeffrey Yasskin, 2015-08-13 21:32:53]

LGTM

https://codereview.chromium.org/1286883002/diff/60001/content/browser/bluetoo...
File content/browser/bluetooth/bluetooth_dispatcher_host.cc (right):

https://codereview.chromium.org/1286883002/diff/60001/content/browser/bluetoo...
content/browser/bluetooth/bluetooth_dispatcher_host.cc:413: VLOG(1) <<
"Bluetooth Device is no longer in range.";
As discussed over IM, we should drop the VLOGs with constant strings that come
just before a Send(Error(WebBluetoothError)) when the WebBluetoothError is
equivalent to the string.

https://codereview.chromium.org/1286883002/diff/60001/content/browser/bluetoo...
content/browser/bluetooth/bluetooth_dispatcher_host.cc:456: VLOG(1) << "No GATT
Characteristic with UUID: " << characteristic_uuid;
This one's probably also equivalent to its rejection message, since the caller
has the UUID they passed in.

https://codereview.chromium.org/1286883002/diff/60001/tools/metrics/histogram...
File tools/metrics/histograms/histograms.xml (right):

https://codereview.chromium.org/1286883002/diff/60001/tools/metrics/histogram...
tools/metrics/histograms/histograms.xml:2803: +    a 32-bit hash of the UUID.
Used to know what types of characteristics to
31-bit?

https://codereview.chromium.org/1286883002/diff/60001/tools/metrics/histogram...
tools/metrics/histograms/histograms.xml:59628: +  <int value="2140490935"
label="gatt.service_changed"/>
Thanks for generating all of these.

[ortuno, 2015-08-14 16:23:35]

Thanks!

https://codereview.chromium.org/1286883002/diff/60001/content/browser/bluetoo...
File content/browser/bluetooth/bluetooth_dispatcher_host.cc (right):

https://codereview.chromium.org/1286883002/diff/60001/content/browser/bluetoo...
content/browser/bluetooth/bluetooth_dispatcher_host.cc:413: VLOG(1) <<
"Bluetooth Device is no longer in range.";
On 2015/08/13 at 21:32:53, Jeffrey Yasskin wrote:
> As discussed over IM, we should drop the VLOGs with constant strings that come
just before a Send(Error(WebBluetoothError)) when the WebBluetoothError is
equivalent to the string.

Done.

https://codereview.chromium.org/1286883002/diff/60001/content/browser/bluetoo...
content/browser/bluetooth/bluetooth_dispatcher_host.cc:456: VLOG(1) << "No GATT
Characteristic with UUID: " << characteristic_uuid;
On 2015/08/13 at 21:32:52, Jeffrey Yasskin wrote:
> This one's probably also equivalent to its rejection message, since the caller
has the UUID they passed in.

Removed.

https://codereview.chromium.org/1286883002/diff/60001/tools/metrics/histogram...
File tools/metrics/histograms/histograms.xml (right):

https://codereview.chromium.org/1286883002/diff/60001/tools/metrics/histogram...
tools/metrics/histograms/histograms.xml:2803: +    a 32-bit hash of the UUID.
Used to know what types of characteristics to
On 2015/08/13 at 21:32:53, Jeffrey Yasskin wrote:
> 31-bit?

Done.

https://codereview.chromium.org/1286883002/diff/60001/tools/metrics/histogram...
tools/metrics/histograms/histograms.xml:59628: +  <int value="2140490935"
label="gatt.service_changed"/>
On 2015/08/13 at 21:32:53, Jeffrey Yasskin wrote:
> Thanks for generating all of these.

No prob :)

[ortuno, 2015-08-14 16:23:52]

ortuno@chromium.org changed reviewers:
+ asvitkine@chromium.org

[ortuno, 2015-08-14 16:23:53]

@asvitkine: PTAL at histograms.xml

[Alexei Svitkine (slow), 2015-08-14 16:32:27]

lgtm

[ortuno, 2015-08-14 16:37:09]

ortuno@chromium.org changed reviewers:
+ scheib@chromium.org

[ortuno, 2015-08-14 16:37:09]

@scheib: PTAL

[scheib, 2015-08-14 17:45:52]

LGTM

[ortuno, 2015-08-14 17:47:16]

The CQ bit was checked by ortuno@chromium.org

[ortuno, 2015-08-14 17:47:17]

The patchset sent to the CQ was uploaded after l-g-t-m from
jyasskin@chromium.org, asvitkine@chromium.org
Link to the patchset: https://codereview.chromium.org/1286883002/#ps120001
(title: "Fix Typoe")

[commit-bot: I haz the power, 2015-08-14 17:47:34]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1286883002/120001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1286883002/120001

[commit-bot: I haz the power, 2015-08-14 18:57:10]

Committed patchset #5 (id:120001)

[commit-bot: I haz the power, 2015-08-14 18:57:48]

Patchset 5 (id:??) landed as
https://crrev.com/dd0208e1701d7fee6b8104f19bda9a817924c4a3
Cr-Commit-Position: refs/heads/master@{#343451}