Convert LoadTimeExtension to gin::Wrappable

Convert LoadTimeExtension to gin::Wrappable

BUG=

[meacer, 2016-03-02 00:37:39]

meacer@chromium.org changed reviewers:
+ jochen@chromium.org

[meacer, 2016-03-02 00:37:39]

jochen, can you PTAL?

This adds the properties under chrome.loadTimesController instead of just
chrome. I haven't figured out how to add them to simply chrome so far.

[jochen (gone - plz use gerrit), 2016-03-02 11:00:45]

jochen@chromium.org changed reviewers:
+ esprehn@chromium.org, haraken@chromium.org

[jochen (gone - plz use gerrit), 2016-03-02 11:00:45]

thanks for doing this

I didn't realize that we expose this to all websites, and not just when a
certain command line flag is set.

I'd rather have this as an IDL defined Web API in Chrome. Elliot/Kentaro, what
do you think?

[haraken, 2016-03-02 13:37:21]

On 2016/03/02 11:00:45, jochen wrote:
> thanks for doing this
> 
> I didn't realize that we expose this to all websites, and not just when a
> certain command line flag is set.
> 
> I'd rather have this as an IDL defined Web API in Chrome. Elliot/Kentaro, what
> do you think?

+1. I'm a fan of describing all web-exposed features in IDL files.

[esprehn, 2016-03-02 17:20:15]

On 2016/03/02 at 13:37:21, haraken wrote:
> On 2016/03/02 11:00:45, jochen wrote:
> > thanks for doing this
> > 
> > I didn't realize that we expose this to all websites, and not just when a
> > certain command line flag is set.
> > 
> > I'd rather have this as an IDL defined Web API in Chrome. Elliot/Kentaro,
what
> > do you think?
> 
> +1. I'm a fan of describing all web-exposed features in IDL files.

Yeah let's move this into blink.

[meacer, 2016-03-09 21:56:40]

On 2016/03/02 17:20:15, esprehn wrote:
> On 2016/03/02 at 13:37:21, haraken wrote:
> > On 2016/03/02 11:00:45, jochen wrote:
> > > thanks for doing this
> > > 
> > > I didn't realize that we expose this to all websites, and not just when a
> > > certain command line flag is set.
> > > 
> > > I'd rather have this as an IDL defined Web API in Chrome. Elliot/Kentaro,
> what
> > > do you think?
> > 
> > +1. I'm a fan of describing all web-exposed features in IDL files.
> 
> Yeah let's move this into blink.

Tracking at crbug.com/593476 now