Add ZoomLevelChanged and DidChangeScrollOffset to RenderViewObserver

Add ZoomLevelChanged and DidChangeScrollOffset to RenderViewObserver

Add ZoomLevelChanged and DidChangeScrollOffset to RenderViewObserver and setup the new Autofill UI to use them to detect when the why content on a page has shifted and any visible popup should be hidden.

BUG=103564
TEST=When using the new Autofill UI scrolling will now cause any visible popups to disappear

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=133924

[csharp, 2012-04-24 18:31:23]

Since the change was so small I merged the modification of renderviewobserver
and the autofillagent using it.

[Ilya Sherman, 2012-04-24 20:15:29]

+jam for content/ review

Is a mouse wheel event always generated when the page scrolls, or is it only
when the page is scrolled using a mousewheel?  For example, what if I use the
keyboard to scroll the page -- is that not possible due to the way we're
intercepting keyboard events?

If mouse wheel events are the only ones we need to care about for scrolling,
then LGTM.

https://chromiumcodereview.appspot.com/10218001/diff/1/chrome/renderer/autofi...
File chrome/renderer/autofill/autofill_agent.cc (right):

https://chromiumcodereview.appspot.com/10218001/diff/1/chrome/renderer/autofi...
chrome/renderer/autofill/autofill_agent.cc:160: // Any time the page scroll any
Autofill popups should be hidden.
nit: Perhaps mention why this only needs to happen when using the new UI.

[csharp, 2012-04-24 20:22:39]

If the popup is visible then the user has selected an input element, which means
all there keyboard presses are handled by that elements (up, down, page up and
page down) so the frame can't move, so the only way for the page to hide when
the popup is visible is via the scroll wheel.

http://codereview.chromium.org/10218001/diff/1/chrome/renderer/autofill/autof...
File chrome/renderer/autofill/autofill_agent.cc (right):

http://codereview.chromium.org/10218001/diff/1/chrome/renderer/autofill/autof...
chrome/renderer/autofill/autofill_agent.cc:160: // Any time the page scroll any
Autofill popups should be hidden.
On 2012/04/24 20:15:29, Ilya Sherman wrote:
> nit: Perhaps mention why this only needs to happen when using the new UI.

Done.

[jam, 2012-04-24 23:59:45]

On 2012/04/24 20:15:29, Ilya Sherman wrote:
> +jam for content/ review
> 
> Is a mouse wheel event always generated when the page scrolls, or is it only
> when the page is scrolled using a mousewheel?  

Only for actual mouse wheel events afaik, but should be easy to verify.

What are you doing for scroll events from pages or keyboard?

[csharp, 2012-04-25 14:37:02]

On 2012/04/24 23:59:45, John Abd-El-Malek wrote:
> On 2012/04/24 20:15:29, Ilya Sherman wrote:
> > +jam for content/ review
> > 
> > Is a mouse wheel event always generated when the page scrolls, or is it only
> > when the page is scrolled using a mousewheel?  
> 
> Only for actual mouse wheel events afaik, but should be easy to verify.
> 
> What are you doing for scroll events from pages or keyboard?

I had forgotten scroll events from pages. I've remove DidHandleWheelEvent and
replaced it with DidChangeScrollOffset, which seems to handle all the scrolling
events.

Also added ZoomLevelChanged since the popup should also hide in that case.

[jam, 2012-04-25 15:00:31]

lgtm

[commit-bot: I haz the power, 2012-04-25 15:06:01]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/csharp@chromium.org/10218001/8001

[commit-bot: I haz the power, 2012-04-25 16:26:28]

Change committed as 133924