Adding error enum to be used by PeerConnectionInterface methods.

Adding error enum to be used by PeerConnectionInterface methods.

The enum is at about the same level of detail as DOMExceptions, and I
looked through the spec making sure that chromium will be able to perform
the DOMException mapping for each one.

The new enum is called RtcError and is outside the PeerConnectionInterface
scope, because we may want to use this for things not associated with a
PeerConnection in the future.

This CL doesn't yet use the error enum anywhere; that will probably happen
in follow-up CLs for the individual methods.

BUG=webrtc:6855
Committed: https://crrev.com/3edec7cf1b342e8b76fbf14ba25351f7338c0d42
Cr-Commit-Position: refs/heads/master@{#15526}

[Taylor Brandstetter, 2016-12-08 23:23:40]

deadbeef@webrtc.org changed reviewers:
+ hta@webrtc.org, pthatcher@webrtc.org

[Taylor Brandstetter, 2016-12-08 23:23:40]

PTAL Peter. Also adding Harald since he was involved in this discussion.

[hta-webrtc, 2016-12-09 10:13:16]

Advice. Principle looks good, but code isn't the way I'd have done it.

https://codereview.webrtc.org/2564683002/diff/1/webrtc/api/peerconnectioninte...
File webrtc/api/peerconnectioninterface.h (right):

https://codereview.webrtc.org/2564683002/diff/1/webrtc/api/peerconnectioninte...
webrtc/api/peerconnectioninterface.h:146: enum class RtcError {
Almost every time I've had an error enum, there's been a "kNoError" at value
zero. It catches some errors, and it's occasionally useful to set as a default
or return as a function result.

https://codereview.webrtc.org/2564683002/diff/1/webrtc/api/peerconnectioninte...
webrtc/api/peerconnectioninterface.h:149: UNSUPPORTED_PARAMETER,
Why the ALL_CAPS_YELLING_NAMES?

https://google.github.io/styleguide/cppguide.html#Enumerator_Names says that
it's preferable to name them like constants, not macros.

https://codereview.webrtc.org/2564683002/diff/1/webrtc/api/peerconnectioninte...
webrtc/api/peerconnectioninterface.h:174: 
I've found it wise to add an ostream& operator<< (ostream& stream, RTCError
error) right off the bat.

It turns out that you have to have one of those in order to support RTC_CHECK_EQ
on the type, and people will look at your code strangely if you do
RTC_CHECK(status == RtcError::something).

[Taylor Brandstetter, 2016-12-09 18:39:07]

https://codereview.webrtc.org/2564683002/diff/1/webrtc/api/peerconnectioninte...
File webrtc/api/peerconnectioninterface.h (right):

https://codereview.webrtc.org/2564683002/diff/1/webrtc/api/peerconnectioninte...
webrtc/api/peerconnectioninterface.h:146: enum class RtcError {
On 2016/12/09 10:13:16, hta-webrtc wrote:
> Almost every time I've had an error enum, there's been a "kNoError" at value
> zero. It catches some errors, and it's occasionally useful to set as a default
> or return as a function result.

Ah yes, we do need that. Would have realized the first time I tried to use this.

https://codereview.webrtc.org/2564683002/diff/1/webrtc/api/peerconnectioninte...
webrtc/api/peerconnectioninterface.h:149: UNSUPPORTED_PARAMETER,
On 2016/12/09 10:13:16, hta-webrtc wrote:
> Why the ALL_CAPS_YELLING_NAMES?
> 
> https://google.github.io/styleguide/cppguide.html#Enumerator_Names says that
> it's preferable to name them like constants, not macros.

The Chromium guide says to use this style, and I thought that's what we used:
https://chromium.googlesource.com/chromium/src/+/master/styleguide/c++/c++.md

https://codereview.webrtc.org/2564683002/diff/1/webrtc/api/peerconnectioninte...
webrtc/api/peerconnectioninterface.h:174: 
On 2016/12/09 10:13:16, hta-webrtc wrote:
> I've found it wise to add an ostream& operator<< (ostream& stream, RTCError
> error) right off the bat.
> 
> It turns out that you have to have one of those in order to support
RTC_CHECK_EQ
> on the type, and people will look at your code strangely if you do
> RTC_CHECK(status == RtcError::something).
> 

Done.

[pthatcher1, 2016-12-10 02:14:44]

lgtm

https://codereview.webrtc.org/2564683002/diff/1/webrtc/api/peerconnectioninte...
File webrtc/api/peerconnectioninterface.h (right):

https://codereview.webrtc.org/2564683002/diff/1/webrtc/api/peerconnectioninte...
webrtc/api/peerconnectioninterface.h:149: UNSUPPORTED_PARAMETER,
Yeah, we just had that discussion back in June.   To be sure, I just
double-checked the emails.  We decided to go the CHROME_WAY, for better or
worse.

On 2016/12/09 18:39:07, Taylor Brandstetter wrote:
> On 2016/12/09 10:13:16, hta-webrtc wrote:
> > Why the ALL_CAPS_YELLING_NAMES?
> > 
> > https://google.github.io/styleguide/cppguide.html#Enumerator_Names says that
> > it's preferable to name them like constants, not macros.
> 
> The Chromium guide says to use this style, and I thought that's what we used:
> https://chromium.googlesource.com/chromium/src/+/master/styleguide/c++/c++.md

[hta-webrtc, 2016-12-10 08:11:50]

lgtm

[Taylor Brandstetter, 2016-12-10 18:14:44]

The CQ bit was checked by deadbeef@webrtc.org

[commit-bot: I haz the power, 2016-12-10 18:14:51]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.webrtc.org/...

[commit-bot: I haz the power, 2016-12-10 18:20:00]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-12-10 18:20:01]

Try jobs failed on following builders:
  win_x64_dbg on master.tryserver.webrtc (JOB_FAILED,
http://build.chromium.org/p/tryserver.webrtc/builders/win_x64_dbg/builds/4345)

[Taylor Brandstetter, 2016-12-10 19:06:47]

The CQ bit was checked by deadbeef@webrtc.org

[Taylor Brandstetter, 2016-12-10 19:06:47]

The patchset sent to the CQ was uploaded after l-g-t-m from hta@webrtc.org,
pthatcher@webrtc.org
Link to the patchset: https://codereview.webrtc.org/2564683002/#ps40001 (title:
"Renaming "NO_ERROR" to "NONE" since the former is reserved on Windows...")

[commit-bot: I haz the power, 2016-12-10 19:06:58]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.webrtc.org/...

[commit-bot: I haz the power, 2016-12-10 19:16:48]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-12-10 19:16:49]

Try jobs failed on following builders:
  linux_asan on master.tryserver.webrtc (JOB_FAILED,
http://build.chromium.org/p/tryserver.webrtc/builders/linux_asan/builds/20306)

[Taylor Brandstetter, 2016-12-10 19:19:10]

The CQ bit was checked by deadbeef@webrtc.org

[Taylor Brandstetter, 2016-12-10 19:19:10]

The patchset sent to the CQ was uploaded after l-g-t-m from hta@webrtc.org,
pthatcher@webrtc.org
Link to the patchset: https://codereview.webrtc.org/2564683002/#ps60001 (title:
".")

[commit-bot: I haz the power, 2016-12-10 19:19:18]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.webrtc.org/...

[commit-bot: I haz the power, 2016-12-10 19:44:27]

CQ is committing da patch.

Bot data: {"patchset_id": 60001, "attempt_start_ts": 1481397550367110,
"parent_rev": "20878a7ca0a393aa2298a9110aa468db90c5ec36", "commit_rev":
"624745e79f8d03452b132d33b339502d196a33d8"}

[commit-bot: I haz the power, 2016-12-10 19:44:29]

Description was changed from

==========
Adding error enum to be used by PeerConnectionInterface methods.

The enum is at about the same level of detail as DOMExceptions, and I
looked through the spec making sure that chromium will be able to perform
the DOMException mapping for each one.

The new enum is called RtcError and is outside the PeerConnectionInterface
scope, because we may want to use this for things not associated with a
PeerConnection in the future.

This CL doesn't yet use the error enum anywhere; that will probably happen
in follow-up CLs for the individual methods.

BUG=webrtc:6855
==========

to

==========
Adding error enum to be used by PeerConnectionInterface methods.

The enum is at about the same level of detail as DOMExceptions, and I
looked through the spec making sure that chromium will be able to perform
the DOMException mapping for each one.

The new enum is called RtcError and is outside the PeerConnectionInterface
scope, because we may want to use this for things not associated with a
PeerConnection in the future.

This CL doesn't yet use the error enum anywhere; that will probably happen
in follow-up CLs for the individual methods.

BUG=webrtc:6855

Review-Url: https://codereview.webrtc.org/2564683002
==========

[commit-bot: I haz the power, 2016-12-10 19:44:31]

Committed patchset #4 (id:60001)

[commit-bot: I haz the power, 2016-12-10 19:57:27]

Description was changed from

==========
Adding error enum to be used by PeerConnectionInterface methods.

The enum is at about the same level of detail as DOMExceptions, and I
looked through the spec making sure that chromium will be able to perform
the DOMException mapping for each one.

The new enum is called RtcError and is outside the PeerConnectionInterface
scope, because we may want to use this for things not associated with a
PeerConnection in the future.

This CL doesn't yet use the error enum anywhere; that will probably happen
in follow-up CLs for the individual methods.

BUG=webrtc:6855

Review-Url: https://codereview.webrtc.org/2564683002
==========

to

==========
Adding error enum to be used by PeerConnectionInterface methods.

The enum is at about the same level of detail as DOMExceptions, and I
looked through the spec making sure that chromium will be able to perform
the DOMException mapping for each one.

The new enum is called RtcError and is outside the PeerConnectionInterface
scope, because we may want to use this for things not associated with a
PeerConnection in the future.

This CL doesn't yet use the error enum anywhere; that will probably happen
in follow-up CLs for the individual methods.

BUG=webrtc:6855

Committed: https://crrev.com/3edec7cf1b342e8b76fbf14ba25351f7338c0d42
Cr-Commit-Position: refs/heads/master@{#15526}
==========

[commit-bot: I haz the power, 2016-12-10 19:57:28]

Patchset 4 (id:??) landed as
https://crrev.com/3edec7cf1b342e8b76fbf14ba25351f7338c0d42
Cr-Commit-Position: refs/heads/master@{#15526}