Aggregate parameters through mappings.

Aggregate parameters through mappings.

This will allow to do something like:
- Pass generic parameters to mojo:window_manager
- Pass specific parameters to the final implementation

It will also ensure that when mappings are present, the arguments an
application receive do not depend on the URL used to connect to it the first
time.

R=davemoore@chromium.org

Committed: https://chromium.googlesource.com/external/mojo/+/1a5952eb25c1dccb29a929542453bdaf6cdc2d42

[DaveMoore, 2015-03-23 15:47:48]

lgtm

While I think this is the best thing to do, note that some applications use
their arguments positionally. This is unlikely to work well with those apps.

https://codereview.chromium.org/1025603004/diff/20001/shell/application_manag...
File shell/application_manager/application_manager.cc (right):

https://codereview.chromium.org/1025603004/diff/20001/shell/application_manag...
shell/application_manager/application_manager.cc:33: if (!v1.size()) {
Nit: no braces

https://codereview.chromium.org/1025603004/diff/20001/shell/application_manag...
shell/application_manager/application_manager.cc:37: return v1;
Nit: ditto

[qsr, 2015-03-23 16:04:13]

On 2015/03/23 15:47:48, DaveMoore wrote:
> lgtm
> 
> While I think this is the best thing to do, note that some applications use
> their arguments positionally. This is unlikely to work well with those apps.

 Well, it will work as long as there is no multiple arguments for those apps in
the mapping chain. If there is, we were already broken anyway. But I agree that
mojo app in general should not use positional arguments.

[qsr, 2015-03-23 16:04:38]

https://codereview.chromium.org/1025603004/diff/20001/shell/application_manag...
File shell/application_manager/application_manager.cc (right):

https://codereview.chromium.org/1025603004/diff/20001/shell/application_manag...
shell/application_manager/application_manager.cc:33: if (!v1.size()) {
On 2015/03/23 15:47:48, DaveMoore wrote:
> Nit: no braces

Done.

https://codereview.chromium.org/1025603004/diff/20001/shell/application_manag...
shell/application_manager/application_manager.cc:37: return v1;
On 2015/03/23 15:47:48, DaveMoore wrote:
> Nit: ditto

Done.

[qsr, 2015-03-23 16:04:50]

Committed patchset #3 (id:40001) manually as
1a5952eb25c1dccb29a929542453bdaf6cdc2d42 (presubmit successful).