cc: Copy category/arg names for tracing in BeginFrameTracker.

cc: Copy arg names for tracing in BeginFrameTracker.

Tracing does not copy arg names by default assuming them to be global
constants. BeginFrameTracker passes the location string to tracing but
does not copy them leading to a crash later.

BUG=601459
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel

Committed: https://crrev.com/c289ed1dff66e6d902c6d7e46aac5926fb52ded8
Cr-Commit-Position: refs/heads/master@{#389179}

[sunnyps, 2016-04-12 01:53:01]

Description was changed from

==========
cc: Copy category/arg names for tracing in BeginFrameTracker.

Tracing does not copy category/arg names by default assuming them to
be global constants. BeginFrameTracker passes the location string to
tracing but does not copy them leading to a crash later.

BUG=601459
==========

to

==========
cc: Copy category/arg names for tracing in BeginFrameTracker.

Tracing does not copy category/arg names by default assuming them to
be global constants. BeginFrameTracker passes the location string to
tracing but does not copy them leading to a crash later.

BUG=601459
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel
==========

[sunnyps, 2016-04-12 02:00:17]

Description was changed from

==========
cc: Copy category/arg names for tracing in BeginFrameTracker.

Tracing does not copy category/arg names by default assuming them to
be global constants. BeginFrameTracker passes the location string to
tracing but does not copy them leading to a crash later.

BUG=601459
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel
==========

to

==========
cc: Copy category/arg names for tracing in BeginFrameTracker.

Tracing does not copy category/arg names by default assuming them to
be global constants. BeginFrameTracker passes the location string to
tracing but does not copy them leading to a crash later.

Also removes incorrect usage of flow events.

BUG=601459
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel
==========

[sunnyps, 2016-04-12 02:04:44]

sunnyps@chromium.org changed reviewers:
+ skyostil@chromium.org

[sunnyps, 2016-04-12 02:04:44]

PTAL

This fixes a use-after-free bug with using non constant string for tracing
categories. I also noticed an incorrect use of flow events here. The original
intent seems to have been to trace a begin frame across multiple layers but
there's no TRACE_FLOW_EVENT_BEGIN/END and we really can't support tracing begin
frames that way because they don't have a unique identity (maybe frame time is a
unique identity but I won't bet on it).

[Sami, 2016-04-12 10:14:38]

lgtm. Thanks for cleaning up the flow usage too.

[Sami, 2016-04-12 10:15:58]

Just to mention an alternative, the char* members of tracked_objects::Location()
are long lived so they could be passed to tracing without making copies.

[sunnyps, 2016-04-15 20:40:35]

On 2016/04/12 10:15:58, Sami wrote:
> Just to mention an alternative, the char* members of
tracked_objects::Location()
> are long lived so they could be passed to tracing without making copies.

I considered that but those strings are formatted together in
Location::ToString() and the result is not long lived.

I also found the begin/end calls for the flow event (not sure how I missed them)
so I've restored the flow step.

[sunnyps, 2016-04-15 20:41:03]

The CQ bit was checked by sunnyps@chromium.org

[sunnyps, 2016-04-15 20:41:03]

The patchset sent to the CQ was uploaded after l-g-t-m from
skyostil@chromium.org
Link to the patchset: https://codereview.chromium.org/1876413003/#ps40001
(title: " ")

[commit-bot: I haz the power, 2016-04-15 20:41:18]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1876413003/40001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1876413003/40001

[commit-bot: I haz the power, 2016-04-15 20:49:37]

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

[commit-bot: I haz the power, 2016-04-15 20:49:38]

Try jobs failed on following builders:
  mac_chromium_compile_dbg_ng on tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_comp...)

[sunnyps, 2016-04-15 21:27:06]

Description was changed from

==========
cc: Copy category/arg names for tracing in BeginFrameTracker.

Tracing does not copy category/arg names by default assuming them to
be global constants. BeginFrameTracker passes the location string to
tracing but does not copy them leading to a crash later.

Also removes incorrect usage of flow events.

BUG=601459
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel
==========

to

==========
cc: Copy arg names for tracing in BeginFrameTracker.

Tracing does not copy arg names by default assuming them to be global
constants. BeginFrameTracker passes the location string to tracing but
does not copy them leading to a crash later.

BUG=601459
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel
==========

[sunnyps, 2016-04-18 23:57:27]

The CQ bit was checked by sunnyps@chromium.org

[sunnyps, 2016-04-18 23:57:28]

The patchset sent to the CQ was uploaded after l-g-t-m from
skyostil@chromium.org
Link to the patchset: https://codereview.chromium.org/1876413003/#ps60001
(title: "use TRACE_EVENT_COPY... instead of TRACE_STR_COPY")

[commit-bot: I haz the power, 2016-04-18 23:58:16]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1876413003/60001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1876413003/60001

[commit-bot: I haz the power, 2016-04-19 01:11:23]

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

[commit-bot: I haz the power, 2016-04-19 01:11:24]

Try jobs failed on following builders:
  linux_android_rel_ng on tryserver.chromium.android (JOB_FAILED,
https://build.chromium.org/p/tryserver.chromium.android/builders/linux_androi...)

[sunnyps, 2016-04-19 01:23:42]

The CQ bit was checked by sunnyps@chromium.org

[commit-bot: I haz the power, 2016-04-19 01:23:55]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1876413003/60001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1876413003/60001

[commit-bot: I haz the power, 2016-04-19 01:38:24]

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

[commit-bot: I haz the power, 2016-04-19 01:38:25]

Try jobs failed on following builders:
  linux_android_rel_ng on tryserver.chromium.android (JOB_FAILED,
https://build.chromium.org/p/tryserver.chromium.android/builders/linux_androi...)

[sunnyps, 2016-04-22 01:02:43]

The CQ bit was checked by sunnyps@chromium.org

[commit-bot: I haz the power, 2016-04-22 01:03:06]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1876413003/60001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1876413003/60001

[commit-bot: I haz the power, 2016-04-22 02:07:47]

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

[commit-bot: I haz the power, 2016-04-22 02:07:48]

Try jobs failed on following builders:
  linux_android_rel_ng on tryserver.chromium.android (JOB_FAILED,
https://build.chromium.org/p/tryserver.chromium.android/builders/linux_androi...)

[sunnyps, 2016-04-22 18:27:00]

The CQ bit was checked by sunnyps@chromium.org

[commit-bot: I haz the power, 2016-04-22 18:27:54]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1876413003/60001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1876413003/60001

[commit-bot: I haz the power, 2016-04-22 18:35:19]

Description was changed from

==========
cc: Copy arg names for tracing in BeginFrameTracker.

Tracing does not copy arg names by default assuming them to be global
constants. BeginFrameTracker passes the location string to tracing but
does not copy them leading to a crash later.

BUG=601459
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel
==========

to

==========
cc: Copy arg names for tracing in BeginFrameTracker.

Tracing does not copy arg names by default assuming them to be global
constants. BeginFrameTracker passes the location string to tracing but
does not copy them leading to a crash later.

BUG=601459
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel
==========

[commit-bot: I haz the power, 2016-04-22 18:35:20]

Committed patchset #4 (id:60001)

[commit-bot: I haz the power, 2016-04-22 19:50:17]

Description was changed from

==========
cc: Copy arg names for tracing in BeginFrameTracker.

Tracing does not copy arg names by default assuming them to be global
constants. BeginFrameTracker passes the location string to tracing but
does not copy them leading to a crash later.

BUG=601459
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel
==========

to

==========
cc: Copy arg names for tracing in BeginFrameTracker.

Tracing does not copy arg names by default assuming them to be global
constants. BeginFrameTracker passes the location string to tracing but
does not copy them leading to a crash later.

BUG=601459
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel

Committed: https://crrev.com/c289ed1dff66e6d902c6d7e46aac5926fb52ded8
Cr-Commit-Position: refs/heads/master@{#389179}
==========

[commit-bot: I haz the power, 2016-04-22 19:50:18]

Patchset 4 (id:??) landed as
https://crrev.com/c289ed1dff66e6d902c6d7e46aac5926fb52ded8
Cr-Commit-Position: refs/heads/master@{#389179}