automation: always use latest Windows AMI
The old AMI isn't available any more.
We seem to run into this problem every few months. Amazon (or
Microsoft) appears to be removing the old AMIs when they are
superseded or something. Let's give up on tracking known images
and switch the image selection logic to use the latest published
image.
Differential Revision: https://phab.mercurial-scm.org/D8465
https://bz.mercurial-scm.org/522
In the merge below, the file "foo" has the same contents in both
parents, but if we look at the file-level history, we'll notice that
the version in p1 is an ancestor of the version in p2. This test makes
sure that we'll use the version from p2 in the manifest of the merge
revision.
$ hg init
$ echo foo > foo
$ hg ci -qAm 'add foo'
$ echo bar >> foo
$ hg ci -m 'change foo'
$ hg backout -r tip -m 'backout changed foo'
reverting foo
changeset 2:4d9e78aaceee backs out changeset 1:b515023e500e
$ hg up -C 0
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ touch bar
$ hg ci -qAm 'add bar'
$ hg merge --debug
resolving manifests
branchmerge: True, force: False, partial: False
ancestor: bbd179dfa0a7, local: 71766447bdbb+, remote: 4d9e78aaceee
foo: remote is newer -> g
getting foo
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg debugstate | grep foo
m 0 -2 unset foo
$ hg st -A foo
M foo
$ hg ci -m 'merge'
$ hg manifest --debug | grep foo
c6fc755d7e68f49f880599da29f15add41f42f5a 644 foo
$ hg debugindex foo
rev linkrev nodeid p1 p2
0 0 2ed2a3912a0b 000000000000 000000000000
1 1 6f4310b00b9a 2ed2a3912a0b 000000000000
2 2 c6fc755d7e68 6f4310b00b9a 000000000000