EC2 'attaching' state is not reported for attaching volumes

[Feodor Tersin]

When volume is attaching AWS reports 'attaching' in the volume attachment info:
VOLUME vol-b6baa9ff 1 us-east-1b in-use 2014-08-11T15:34:38.090Z
ATTACHMENT vol-b6baa9ff i-afcc1f85 /dev/sdd attaching 2014-08-11T15:41:24.000Z

But Nova EC2 doesn't do it:
VOLUME vol-00000001 1 nova in-use 2014-08-10T19:51:06.000000
ATTACHMENT vol-00000001 None None None None

Also instance BDM has wrong volume state. AWS returns 'attaching':
  <deviceName>/dev/sdf</deviceName>
  <ebs>
      <volumeId>vol-f4524dbd</volumeId>
      <status>attaching</status>
      <attachTime>2014-08-12T20:24:13.000Z</attachTime>
      <deleteOnTermination>false</deleteOnTermination>
  </ebs>

But Nova EC2 returns 'detached':
  <deviceName>/dev/vdf</deviceName>
  <ebs>
    <status>detached</status>
    <deleteOnTermination>false</deleteOnTermination>
    <volumeId>vol-00000001</volumeId>
    <attachTime/>
  </ebs>

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/113790

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/113790
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=c1f9ab8d3dbc695f304c70c91058f888d5c134f9
Submitter: Jenkins
Branch: master

commit c1f9ab8d3dbc695f304c70c91058f888d5c134f9
Author: Feodor Tersin <email address hidden>
Date: Wed Aug 13 10:02:10 2014 +0400

    Fix EC2 volume attachment state at attaching stage.

    While volume is still attaching/detaching, AWS reports 'attaching'/
    'detaching' states in the volume attachment info and instance bdm.
    But Nova EC2 reports None, 'attached', or 'detached' states.

    This fix set 'attaching'/'detaching' states in output results when
    it's possible and while corresponding process is still active.

    Change-Id: I61ef5afb2c3dea2a931dbf18a8a428460ce9cc2e
    Closes-Bug: #1355285