Issue #1486 - Move PassthroughAPP code to its own directory

Issue #1486 - Move PassthroughAPP code to its own directory

Move the current PassthroughAPP code into its own directory
'src/plugin/passthroughapp'.

This is a preliminary change. The current code we have for PassthroughAPP is
not fully third-party code at present. It's a combination of an older version
plus our own modifications. After #1484 is done, we can complete #1486 and
move it into 'third_party/passthroughapp'.

[Eric, 2015-11-23 13:02:21]

The review tool is showing "-1" lines changed for "0" lines changed for the
renamed files.

[sergei, 2015-11-23 13:59:37]

LGTM

Eric wrote:
>  After #1484 is done, we can complete #1486 and move it into
'third_party/passthroughapp'.

We can merge it now and then do #1484 and get the same state. So, we need to
change the commit message or to get #1484 done firstly.

[Eric, 2015-11-23 14:11:31]

On 2015/11/23 13:59:37, sergei wrote:
> We can merge it now and then do #1484 and get the same state. So, we need to
> change the commit message or to get #1484 done firstly.

My plan is to fix #1484 using the present code and not combine it with an update
to PassthroughAPP. Fixing #1484 does not require an update, nor does it
interfere with it. Splitting these up will allow the review to proceed more
cleanly, since no one will have to figure out why a particular change is present
in any given change set. It's one of the reasons I put up the present review.
When we update the code to PassthroughAPP, it won't be combined with a file
rename/relocate.

[Oleksandr, 2015-11-24 10:52:10]

LGTM