Make the MessageLoop PostTask ID more unique.

Make the MessageLoop PostTask ID more unique.

When looking at chrome://tracing we were seeing duplicate IDs linking PostTask
flow events. This CL is an attempt to fix that issue.

Currently we take the sequence_num and shift it 32 bits to the left in a uint64.
When then OR the intptr_t of this into that number. On x86_64 the
sizeof(intptr_t) is 8bytes. This means, we'll be ORing the top 32 bits of the
this address with the sequence_num.

This CL takes the this pointer and removes the top 32bits before ORing with the
sequence_num. So, we get the sequence_num followed by the bottom 32bits of the
this pointer.

BUG=
TBR=darin@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=218403

[nduca, 2013-08-13 18:01:18]

lgtm

[dsinclair, 2013-08-13 18:23:48]

brettw PTAL for base/ OWNERS.

[dsinclair, 2013-08-14 19:08:27]

darin for base/ OWNERS

[dsinclair, 2013-08-16 14:43:32]

ping

[nduca, 2013-08-17 01:19:11]

Lets TBR=darin this and I'll take responsibility if anyone flips. base/ OWNERS
are hard to come by right now and this is low risk and in keeping with my
understanding of the spirit of base.

[commit-bot: I haz the power, 2013-08-17 02:41:26]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/dsinclair@chromium.org/23095002/1

[commit-bot: I haz the power, 2013-08-17 03:16:24]

Retried try job too often on ios_dbg_simulator for step(s) media_unittests
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=ios_dbg_si...

[commit-bot: I haz the power, 2013-08-17 03:20:37]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/dsinclair@chromium.org/23095002/1

[commit-bot: I haz the power, 2013-08-17 03:44:18]

Retried try job too often on ios_dbg_simulator for step(s) media_unittests
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=ios_dbg_si...

[commit-bot: I haz the power, 2013-08-17 16:52:54]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/dsinclair@chromium.org/23095002/1

[commit-bot: I haz the power, 2013-08-17 17:14:26]

Retried try job too often on ios_dbg_simulator for step(s) media_unittests
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=ios_dbg_si...

[commit-bot: I haz the power, 2013-08-17 17:57:46]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/dsinclair@chromium.org/23095002/1

[commit-bot: I haz the power, 2013-08-17 18:19:16]

Retried try job too often on ios_dbg_simulator for step(s) media_unittests
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=ios_dbg_si...

[commit-bot: I haz the power, 2013-08-19 17:11:55]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/dsinclair@chromium.org/23095002/1

[commit-bot: I haz the power, 2013-08-20 01:49:39]

Change committed as 218403