Clarify when what notifications are send when a window object is cleared

Clarify when what notifications are send when a window object is cleared
    
There are two different events that most of the time coincide: a
JavaScript wrapper for a DOMWindow is created, and a new Document is
installed on the DOMWindow.
    
Sometimes, only the former happens, e.g. an iframe with an image as src
doesn't have an document.
    
However, for the embedder, this difference doesn't matter. It's in both
cases possible (and necessary) to install additional hooks on the
windows object.
    
Last but not least, we should never notify the embedder for changes in
isolated worlds. An embedder that is interested in these signals should
listen didCreateScriptContext/willReleaseScriptContext.
    
BUG=none
R=yurys@chromium.org,dcarney@chromium.org

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=173621

[jochen (gone - plz use gerrit), 2014-05-07 12:26:50]

ptal

[dcarney, 2014-05-07 13:50:55]

lgtm

[yurys, 2014-05-07 14:14:07]

lgtm

https://codereview.chromium.org/146693005/diff/40001/Source/core/loader/Frame...
File Source/core/loader/FrameLoader.cpp (right):

https://codereview.chromium.org/146693005/diff/40001/Source/core/loader/Frame...
Source/core/loader/FrameLoader.cpp:1399: // FIXME: Why isn't the inspector
notified of this?
Looks like a bug to me. InspectorController used to be notified from this method
too but the code was removed in
https://src.chromium.org/viewvc/blink?revision=165056&view=revision

[jochen (gone - plz use gerrit), 2014-05-07 15:10:50]

On 2014/05/07 14:14:07, yurys wrote:
> lgtm
> 
>
https://codereview.chromium.org/146693005/diff/40001/Source/core/loader/Frame...
> File Source/core/loader/FrameLoader.cpp (right):
> 
>
https://codereview.chromium.org/146693005/diff/40001/Source/core/loader/Frame...
> Source/core/loader/FrameLoader.cpp:1399: // FIXME: Why isn't the inspector
> notified of this?
> Looks like a bug to me. InspectorController used to be notified from this
method
> too but the code was removed in
> https://src.chromium.org/viewvc/blink?revision=165056&view=revision

hum, i guess i'll put it back in and don't rename the inspector methods

[jochen (gone - plz use gerrit), 2014-05-08 06:34:33]

The CQ bit was checked by jochen@chromium.org

[jochen (gone - plz use gerrit), 2014-05-08 06:34:53]

The CQ bit was unchecked by jochen@chromium.org

[jochen (gone - plz use gerrit), 2014-05-08 06:35:24]

The CQ bit was checked by jochen@chromium.org

[commit-bot: I haz the power, 2014-05-08 06:36:08]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/jochen@chromium.org/146693005/60001

[commit-bot: I haz the power, 2014-05-08 07:55:12]

FYI, CQ is re-trying this CL (attempt #1).
Please consider checking whether the failures are real,
and report flakes to chrome-troopers@google.com.
The failing builders are:
  linux_blink_dbg on tryserver.blink
  linux_blink_rel on tryserver.blink
  mac_blink_rel on tryserver.blink
  win_blink_rel on tryserver.blink

[jochen (gone - plz use gerrit), 2014-05-08 08:32:03]

The CQ bit was unchecked by jochen@chromium.org

[jochen (gone - plz use gerrit), 2014-05-08 08:34:30]

On 2014/05/08 07:55:12, I haz the power (commit-bot) wrote:
> FYI, CQ is re-trying this CL (attempt #1).
> Please consider checking whether the failures are real,
> and report flakes to mailto:chrome-troopers@google.com.
> The failing builders are:
>   linux_blink_dbg on tryserver.blink
>   linux_blink_rel on tryserver.blink
>   mac_blink_rel on tryserver.blink
>   win_blink_rel on tryserver.blink

hum, so actually, this breaks the inspector.

I also figured out why I dropped this in the other CL: we used to use the
existingShellWorkaroundWorld from ScriptController instead of the main world,
and the inspector code would ignore signals from that world.

[jochen (gone - plz use gerrit), 2014-05-08 08:35:38]

The CQ bit was checked by jochen@chromium.org

[commit-bot: I haz the power, 2014-05-08 08:36:21]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/jochen@chromium.org/146693005/40001

[commit-bot: I haz the power, 2014-05-08 08:52:53]

Change committed as 173621