DO NOT COMMIT

DO NOT COMMIT

Tentative CL to explain logic to save favicon during distillation.
The main point is the subclass of WebFaviconDriver::FaviconUrlUpdated() by a method saving the page url.

[gambard, 2016-11-30 17:14:44]

Description was changed from

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DO NOT COMMIT

Tentative CL to explain logic to save favicon during distillation.
==========

to

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DO NOT COMMIT

Tentative CL to explain logic to save favicon during distillation.
The main point is the subclass of WebFaviconDriver::FaviconUrlUpdated() by a
method saving the page url.
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[gambard, 2016-11-30 17:16:56]

gambard@chromium.org changed reviewers:
+ eugenebut@chromium.org, kkhorimoto@chromium.org

[gambard, 2016-11-30 17:16:56]

PTAL.
This an idea of how it is possible to get the favicon using the standard
pipeline of WebState by subclassing WebFaviconDriver, mainly for the
WebStateObserver behavior.
It needs to be friend with the WebFaviconDriver as it has a private
constructor/destructor.

The class names are terrible and the code can greatly be optimized. This is for
comments about the approach.

What do you think?

[kkhorimoto, 2016-11-30 18:29:37]

I've commented on your original CL after taking a look at this one.  We should
attempt to debug why GetActiveURL() is not behaving as intended instead of
creating this workaround using subclassing.  If we discover that the visible
NavigationItem's being null is expected (which I don't think is the case), then
we can revisit this approach.