Changes to content/ to facilitate new zoom extension API (work in progress)

Some minimal changes to content/ needed to facilitate the new zoom extension API, which is outlined in: https://docs.google.com/a/chromium.org/document/d/1sCZjx1J3_M2a02T8NXd-ufGKZDoBHI5Ixis1DaGLQCA/edit?usp=sharing. 

BUG=30583

[Avi (use Gerrit), 2014-04-12 04:06:48]

John likes looking at content/public.

[jam, 2014-05-01 23:21:12]

just a small comment

can i see the chrome calling code somewhere?

https://codereview.chromium.org/226523006/diff/1/content/browser/web_contents...
File content/browser/web_contents/web_contents_impl.cc (right):

https://codereview.chromium.org/226523006/diff/1/content/browser/web_contents...
content/browser/web_contents/web_contents_impl.cc:1019: temporary_zoom_settings_
= temporary_zoom_settings;
seems that HostZoomMap::SetTemporaryZoomLevel should call an (internal)
WebContentsImpl to do this and we can avoid the public api on WebContents

https://codereview.chromium.org/226523006/diff/1/content/public/browser/host_...
File content/public/browser/host_zoom_map.h (right):

https://codereview.chromium.org/226523006/diff/1/content/public/browser/host_...
content/public/browser/host_zoom_map.h:116: Subscription;
nit: leave as is

[wjmaclean, 2014-05-02 16:14:40]

On 2014/05/01 23:21:12, jam wrote:
> just a small comment
> 
> can i see the chrome calling code somewhere?
> 

The chromium calling code is at https://codereview.chromium.org/232773011/,
though I am in the process of finishing it (it is in an incomplete state at
present).

[jam, 2014-05-02 19:15:04]

On 2014/05/02 16:14:40, wjmaclean wrote:
> On 2014/05/01 23:21:12, jam wrote:
> > just a small comment
> > 
> > can i see the chrome calling code somewhere?
> > 
> 
> The chromium calling code is at https://codereview.chromium.org/232773011/,
> though I am in the process of finishing it (it is in an incomplete state at
> present).

I see. are you sure that this is the final api you'll need from content until
that part is done?

[wjmaclean, 2014-05-08 18:40:48]

On 2014/05/02 19:15:04, jam wrote:
> On 2014/05/02 16:14:40, wjmaclean wrote:
> > On 2014/05/01 23:21:12, jam wrote:
> > > just a small comment
> > > 
> > > can i see the chrome calling code somewhere?
> > > 
> > 
> > The chromium calling code is at https://codereview.chromium.org/232773011/,
> > though I am in the process of finishing it (it is in an incomplete state at
> > present).
> 
> I see. are you sure that this is the final api you'll need from content until
> that part is done?

As I'm inheriting this code, and still on the learning curve, I can't be 100%
sure about that (at least not yet).

[jam, 2014-05-09 17:09:55]

On 2014/05/08 18:40:48, wjmaclean wrote:
> On 2014/05/02 19:15:04, jam wrote:
> > On 2014/05/02 16:14:40, wjmaclean wrote:
> > > On 2014/05/01 23:21:12, jam wrote:
> > > > just a small comment
> > > > 
> > > > can i see the chrome calling code somewhere?
> > > > 
> > > 
> > > The chromium calling code is at
https://codereview.chromium.org/232773011/,
> > > though I am in the process of finishing it (it is in an incomplete state
at
> > > present).
> > 
> > I see. are you sure that this is the final api you'll need from content
until
> > that part is done?
> 
> As I'm inheriting this code, and still on the learning curve, I can't be 100%
> sure about that (at least not yet).

ok, please let me know when the chrome side is done and you know for sure what
we need from the content api

[wjmaclean, 2014-05-28 15:31:52]

Moved to https://codereview.chromium.org/302603012/