Walking heaps from GetProcessHeaps is flaky by design, failing on XP

Walking heaps from GetProcessHeaps is flaky by design, failing on XP

There are two possible race conditions in walking the heaps returned
by GetProcessHeaps and on Windows XP we hit one of these race conditions,
manifested in a crash, on 42 of the last 200 base unittests. Disabling
the test entirely until a better fix is found (or perhaps forever).

The unreliability of the underlying code is acceptable for tracing,
although perhaps not acceptable for tracing on XP given the failure rate.

TBR=sebmarchand@chromium.org,primiano@chromium.org
BUG=487291
Committed: https://crrev.com/089be897821c18207119dfe364f19cfc1876bc82
Cr-Commit-Position: refs/heads/master@{#330423}

[brucedawson, 2015-05-18 20:47:33]

I'm going to commit this to reduce flakiness. A better fix may be appropriate
long-term.

Gotta love Windows APIs that are unreliable by design!

[brucedawson, 2015-05-18 20:47:40]

The CQ bit was checked by brucedawson@chromium.org

[commit-bot: I haz the power, 2015-05-18 20:50:42]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1140943006/1

[commit-bot: I haz the power, 2015-05-18 21:07:28]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-05-18 22:43:34]

Patchset 1 (id:??) landed as
https://crrev.com/089be897821c18207119dfe364f19cfc1876bc82
Cr-Commit-Position: refs/heads/master@{#330423}

[Primiano Tucci (use gerrit), 2015-05-19 09:14:01]

LGTM with sad face (but many thanks for the thorough  explanation in the mail
thread... at least it was funny to realize how that API is so broken).
Up to you guys to figure out what is the best way forward on WinHeap dumper.

[brucedawson1, 2015-05-19 14:18:41]

Listing all heaps is safe, and enumerating a heap is safe, but enumerating all
heaps that you list...

[Sébastien Marchand, 2015-05-25 15:49:39]

On 2015/05/19 14:18:41, brucedawson1 wrote:
> Listing all heaps is safe, and enumerating a heap is safe, but enumerating all
> heaps that you list...

lgtm, thanks fpr the thorough explanation !