Modifies the Instant loader to listen for RENDER_VIEW_HOST_CHANGED notificati...

Modifies the Instant loader to listen for RENDER_VIEW_HOST_CHANGED notifications on Mac.  This notification is sent when a given TabContents changes its renderer, and on Mac we need to call SetTakesFocusOnlyOnMouseDown() on the new RWHV.

BUG=63330
TEST=Type in omnibox with Instant on.  Arrow down through results, then click on preview contents.  Preview contents should not disappear.

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=66312

[sky, 2010-11-16 17:41:04]

http://codereview.chromium.org/5073002/diff/8001/chrome/browser/instant/insta...
File chrome/browser/instant/instant_loader.cc (right):

http://codereview.chromium.org/5073002/diff/8001/chrome/browser/instant/insta...
chrome/browser/instant/instant_loader.cc:394: registrar_.RemoveAll();
Is this needed?

http://codereview.chromium.org/5073002/diff/8001/chrome/browser/instant/insta...
chrome/browser/instant/instant_loader.cc:619: registrar_.Add(
Any reason you put this here instead of when the preview_contents_ is created?

http://codereview.chromium.org/5073002/diff/8001/chrome/browser/instant/insta...
chrome/browser/instant/instant_loader.cc:634: LOG(ERROR) << "New RWHV";
Did you really want the LOG(ERROR)?

[rohitrao (ping after 24h), 2010-11-16 18:33:59]

Moved the notification registration to be up at preview contents creation time. 
Verified that this works.  (I think the RWHV is still NULL at creation time, but
when it is finally connected, we set things up properly as a result of the
notification.)

http://codereview.chromium.org/5073002/diff/8001/chrome/browser/instant/insta...
File chrome/browser/instant/instant_loader.cc (right):

http://codereview.chromium.org/5073002/diff/8001/chrome/browser/instant/insta...
chrome/browser/instant/instant_loader.cc:394: registrar_.RemoveAll();
On 2010/11/16 17:41:05, sky wrote:
> Is this needed?

General paranoia, because we delete preview_contents_ here as well.  I'll remove
it, unless you think it's safer to keep it.

http://codereview.chromium.org/5073002/diff/8001/chrome/browser/instant/insta...
chrome/browser/instant/instant_loader.cc:619: registrar_.Add(
On 2010/11/16 17:41:05, sky wrote:
> Any reason you put this here instead of when the preview_contents_ is created?

Mostly because the notification is so closely associated with the
SetTakesFocusOnlyOnMouseDown() call a few lines up, and this way I have fewer
OS_MACOSX blocks.

I might be able to move this entire block up to be right after we create the
preview contents.  Let me try that.

http://codereview.chromium.org/5073002/diff/8001/chrome/browser/instant/insta...
chrome/browser/instant/instant_loader.cc:634: LOG(ERROR) << "New RWHV";
On 2010/11/16 17:41:05, sky wrote:
> Did you really want the LOG(ERROR)?

No, no I don't =)

[sky, 2010-11-16 18:42:29]

http://codereview.chromium.org/5073002/diff/8001/chrome/browser/instant/insta...
File chrome/browser/instant/instant_loader.cc (right):

http://codereview.chromium.org/5073002/diff/8001/chrome/browser/instant/insta...
chrome/browser/instant/instant_loader.cc:394: registrar_.RemoveAll();
On 2010/11/16 18:33:59, rohitrao wrote:
> On 2010/11/16 17:41:05, sky wrote:
> > Is this needed?
> 
> General paranoia, because we delete preview_contents_ here as well.  I'll
remove
> it, unless you think it's safer to keep it.

You're right, we should keep the explicit remove.

[sky, 2010-11-16 18:43:27]

Add back the explicit remove, and LGTM