i've got most of the framework logic landing via  issue 640401 .  have to refine/check the autotests before finishing it.

otherwise, pending CL is here:
https://chromium-review.googlesource.com/362122

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/platform2/+/d653dbab6abdbaef60081f7be2cb48392a125742

commit d653dbab6abdbaef60081f7be2cb48392a125742
Author: Eric Caruso <ejcaruso@chromium.org>
Date: Mon Apr 03 20:49:56 2017

container_utils: add program to mount image

This small program calls into imageloader to register and load
a component, which is a rootfs image run_oci understands.

BUG= chromium:644347 
TEST=mount_extension_image --name=adb on device with adb
  container extension in user extensions directory

Change-Id: I4ad2f0b8eea30ee9de26035ed14137840b4e3473
Reviewed-on: https://chromium-review.googlesource.com/458563
Commit-Ready: Eric Caruso <ejcaruso@chromium.org>
Tested-by: Eric Caruso <ejcaruso@chromium.org>
Reviewed-by: Dylan Reid <dgreid@chromium.org>

[modify] https://crrev.com/d653dbab6abdbaef60081f7be2cb48392a125742/container_utils/container_utils.gyp
[add] https://crrev.com/d653dbab6abdbaef60081f7be2cb48392a125742/container_utils/mount_extension_image.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/overlays/chromiumos-overlay/+/86b53b0017cbb559a9e577caed73c69d4a0356ec

commit 86b53b0017cbb559a9e577caed73c69d4a0356ec
Author: Eric Caruso <ejcaruso@chromium.org>
Date: Thu Apr 06 23:01:44 2017

container_utils: add mount_extension_image binary

This installs the binary that mounts container images out of
your extensions directory.

CQ-DEPEND=CL:458563
BUG= chromium:644347 
TEST=emerge

Change-Id: I6360cc7c00869d74d4e8e3bffd47b9f1e8aaaebe
Reviewed-on: https://chromium-review.googlesource.com/458736
Commit-Ready: Eric Caruso <ejcaruso@chromium.org>
Tested-by: Eric Caruso <ejcaruso@chromium.org>
Reviewed-by: Stephen Barber <smbarber@chromium.org>

[modify] https://crrev.com/86b53b0017cbb559a9e577caed73c69d4a0356ec/chromeos-base/container_utils/container_utils-9999.ebuild

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/platform2/+/dc1aa7b78e2fdf13484b4b1330508e9a8d0fee4e

commit dc1aa7b78e2fdf13484b4b1330508e9a8d0fee4e
Author: Keshav Santhanam <ksanthanam@google.com>
Date: Wed Apr 12 06:26:03 2017

crosh: Add option for running generic container

This allows for running a program inside a container from crosh.
It starts device_jail_fs via debugd if necessary.

BUG= chromium:644347 
TEST=c adb [args] in crosh

Change-Id: I50ce3a8657e86fae994e614943c4addc44d363b9
Reviewed-on: https://chromium-review.googlesource.com/362122
Commit-Ready: Eric Caruso <ejcaruso@chromium.org>
Tested-by: Eric Caruso <ejcaruso@chromium.org>
Reviewed-by: Dylan Reid <dgreid@chromium.org>

[add] https://crrev.com/dc1aa7b78e2fdf13484b4b1330508e9a8d0fee4e/debugd/src/container_tool.h
[modify] https://crrev.com/dc1aa7b78e2fdf13484b4b1330508e9a8d0fee4e/debugd/src/debug_daemon.cc
[add] https://crrev.com/dc1aa7b78e2fdf13484b4b1330508e9a8d0fee4e/debugd/src/container_tool.cc
[modify] https://crrev.com/dc1aa7b78e2fdf13484b4b1330508e9a8d0fee4e/debugd/dbus_bindings/org.chromium.debugd.xml
[modify] https://crrev.com/dc1aa7b78e2fdf13484b4b1330508e9a8d0fee4e/debugd/src/debug_daemon.h
[modify] https://crrev.com/dc1aa7b78e2fdf13484b4b1330508e9a8d0fee4e/crosh/dev.d/50-crosh.sh
[modify] https://crrev.com/dc1aa7b78e2fdf13484b4b1330508e9a8d0fee4e/debugd/debugd.gyp

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/platform/crosutils/+/c12e11485aac8e59476a40ae3df7a78c2a54bacd

commit c12e11485aac8e59476a40ae3df7a78c2a54bacd
Author: Mike Frysinger <vapier@chromium.org>
Date: Thu May 18 02:06:28 2017

package_to_container: switch to container.json

We need to look for a file with a different name than "manifest.json"
because the CWS does not let us upload extensions with more than one
(the main one), and we want to support more than one, and we want to
use our own format rather than try to merge with the Chrome API.

BUG= chromium:644347 
TEST=creating a new container used container.json

Change-Id: I16de61a8546422688fd7463aed7d5c0ffec6e450
Reviewed-on: https://chromium-review.googlesource.com/506752
Commit-Ready: Mike Frysinger <vapier@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
Reviewed-by: Eric Caruso <ejcaruso@chromium.org>

[modify] https://crrev.com/c12e11485aac8e59476a40ae3df7a78c2a54bacd/package_to_container

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/platform2/+/b5cdb923326276db6a3c7d06b3ff9156bcf0bec6

commit b5cdb923326276db6a3c7d06b3ff9156bcf0bec6
Author: Mike Frysinger <vapier@chromium.org>
Date: Thu May 18 02:06:28 2017

container_utils: rework extension searching

Use the cryptohome APIs to locate active user sessions and their home
directories instead of hardcoding any paths.

Further, change how we walk the Extensions dir.  We need to look for a
file with a different name than "manifest.json" because the CWS does not
let us upload extensions with more than one (the main one), and we want
to support more than one, and we want to use our own format rather than
try to merge with the Chrome API.

BUG= chromium:644347 
TEST=mount_extension_image --name=adb on device with a logged in user and an installed extension

Change-Id: I88109717d4707909b69cdd9740e87593a3ece715
Reviewed-on: https://chromium-review.googlesource.com/505717
Commit-Ready: Mike Frysinger <vapier@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
Reviewed-by: Eric Caruso <ejcaruso@chromium.org>

[modify] https://crrev.com/b5cdb923326276db6a3c7d06b3ff9156bcf0bec6/container_utils/container_utils.gyp
[modify] https://crrev.com/b5cdb923326276db6a3c7d06b3ff9156bcf0bec6/container_utils/mount_extension_image.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/platform2/+/8527ec8fc1df06c4492aa7f7a23e1cec8fdde84b

commit 8527ec8fc1df06c4492aa7f7a23e1cec8fdde84b
Author: Mike Frysinger <vapier@chromium.org>
Date: Wed May 24 05:12:33 2017

container_utils: fix inverted logic

Some last minute refactor request broke this.

BUG= chromium:644347 
TEST=`c adb` in crosh can find the extension again

Change-Id: If29911ca1d454332a81986a9c56b6f6f33cdd7c1
Reviewed-on: https://chromium-review.googlesource.com/513442
Reviewed-by: Eric Caruso <ejcaruso@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>

[modify] https://crrev.com/8527ec8fc1df06c4492aa7f7a23e1cec8fdde84b/container_utils/mount_extension_image.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/platform2/+/8527ec8fc1df06c4492aa7f7a23e1cec8fdde84b

commit 8527ec8fc1df06c4492aa7f7a23e1cec8fdde84b
Author: Mike Frysinger <vapier@chromium.org>
Date: Wed May 24 05:12:33 2017

container_utils: fix inverted logic

Some last minute refactor request broke this.

BUG= chromium:644347 
TEST=`c adb` in crosh can find the extension again

Change-Id: If29911ca1d454332a81986a9c56b6f6f33cdd7c1
Reviewed-on: https://chromium-review.googlesource.com/513442
Reviewed-by: Eric Caruso <ejcaruso@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>

[modify] https://crrev.com/8527ec8fc1df06c4492aa7f7a23e1cec8fdde84b/container_utils/mount_extension_image.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/platform2/+/8527ec8fc1df06c4492aa7f7a23e1cec8fdde84b

commit 8527ec8fc1df06c4492aa7f7a23e1cec8fdde84b
Author: Mike Frysinger <vapier@chromium.org>
Date: Wed May 24 05:12:33 2017

container_utils: fix inverted logic

Some last minute refactor request broke this.

BUG= chromium:644347 
TEST=`c adb` in crosh can find the extension again

Change-Id: If29911ca1d454332a81986a9c56b6f6f33cdd7c1
Reviewed-on: https://chromium-review.googlesource.com/513442
Reviewed-by: Eric Caruso <ejcaruso@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>

[modify] https://crrev.com/8527ec8fc1df06c4492aa7f7a23e1cec8fdde84b/container_utils/mount_extension_image.cc