Move ScopedFileDescriptor to dbus/file_descriptor.h

Move ScopedFileDescriptor to dbus/file_descriptor.h

ScopedFileDescriptor was initially introduced to facilitate the
management of a 'lifeline' FD used when asking permission_broker to
open a port in the device's firewall on CrOS.  It's actually a scoped
wrapper around DBus::FileDescriptor, not a platform file descriptor. I
would like to use it to facilitate some other similar functionality in
which I create a pipe and pass one end over DBus, so it seems like a
good idea to move ScopedFileDescriptor into the dbus library directly.

BUG=chromium:481340
TEST=FirewallHole unit tests still pass
STATUS=Fixed
R=keybuk, reillyg, stevenjb

Committed: https://crrev.com/b44fbaabbe9f91e63ad8aa164609a6b31e0de57e
Cr-Commit-Position: refs/heads/master@{#327089}

[Chris Masone, 2015-04-25 21:15:38]

Steven added for chromeos/ OWNER review.
Scott, please look at the code under dbus/
reillyg@, please look at the firewall_hole.* code.

Also, is there any more testing I could be running? As far as I can tell, this
works fine, but I don't know how to actually integration test it.

[Reilly Grant (use Gerrit), 2015-04-25 21:57:30]

lgtm

If the FirewallHole unit tests pass then you're good.

[stevenjb, 2015-04-27 16:48:09]

lgtm

[keybuk, 2015-04-27 18:02:45]

lgtm

[Chris Masone, 2015-04-27 18:05:55]

The CQ bit was checked by cmasone@chromium.org

[commit-bot: I haz the power, 2015-04-27 18:06:09]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1090243003/1

[commit-bot: I haz the power, 2015-04-27 18:51:12]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-04-27 18:52:13]

Patchset 1 (id:??) landed as
https://crrev.com/b44fbaabbe9f91e63ad8aa164609a6b31e0de57e
Cr-Commit-Position: refs/heads/master@{#327089}

[spang, 2015-04-27 19:44:06]

A revert of this CL (patchset #1 id:1) has been created in
https://codereview.chromium.org/1108893003/ by spang@chromium.org.

The reason for reverting is: Breaks shared_library build with broken exports:

./../dbus/dbus_export.h:20:65: error: ignoring attributes applied to class type
'scoped_ptr<dbus::FileDescriptor, dbus::FileDescriptor::Deleter>' outside of
definition [-Werror=attributes]
 #define CHROME_DBUS_EXPORT __attribute__((visibility("default")))
                                                                 ^
../../dbus/file_descriptor.h:81:57: note: in expansion of macro
'CHROME_DBUS_EXPORT'
     scoped_ptr<FileDescriptor, FileDescriptor::Deleter> CHROME_DBUS_EXPORT;.

[Chris Masone, 2015-04-27 19:45:24]

On 2015/04/27 19:44:06, spang wrote:
> A revert of this CL (patchset #1 id:1) has been created in
> https://codereview.chromium.org/1108893003/ by mailto:spang@chromium.org.
> 
> The reason for reverting is: Breaks shared_library build with broken exports:
> 
> ./../dbus/dbus_export.h:20:65: error: ignoring attributes applied to class
type
> 'scoped_ptr<dbus::FileDescriptor, dbus::FileDescriptor::Deleter>' outside of
> definition [-Werror=attributes]
>  #define CHROME_DBUS_EXPORT __attribute__((visibility("default")))
>                                                                  ^
> ../../dbus/file_descriptor.h:81:57: note: in expansion of macro
> 'CHROME_DBUS_EXPORT'
>      scoped_ptr<FileDescriptor, FileDescriptor::Deleter> CHROME_DBUS_EXPORT;.

Why did none of the trybots catch this?

[stevenjb, 2015-04-27 19:49:05]

On 2015/04/27 19:45:24, Chris Masone wrote:
> On 2015/04/27 19:44:06, spang wrote:
> > A revert of this CL (patchset #1 id:1) has been created in
> > https://codereview.chromium.org/1108893003/ by mailto:spang@chromium.org.
> > 
> > The reason for reverting is: Breaks shared_library build with broken
exports:
> > 
> > ./../dbus/dbus_export.h:20:65: error: ignoring attributes applied to class
> type
> > 'scoped_ptr<dbus::FileDescriptor, dbus::FileDescriptor::Deleter>' outside of
> > definition [-Werror=attributes]
> >  #define CHROME_DBUS_EXPORT __attribute__((visibility("default")))
> >                                                                  ^
> > ../../dbus/file_descriptor.h:81:57: note: in expansion of macro
> > 'CHROME_DBUS_EXPORT'
> >      scoped_ptr<FileDescriptor, FileDescriptor::Deleter>
CHROME_DBUS_EXPORT;.
> 
> Why did none of the trybots catch this?

Sadly we don't have a Chrome OS component build in the CQ trybots. I have been
bit by this a few times myself.