Fix a crash in PasswordManagerExceptionsView

BUG=8345
Added a PasswordManagerTableModelObserver to listen for row count change events.
PasswordManagerView and PasswordManagerExceptionsView are listening to the
event.
Move the |instance_| variable from static global to the respective class to
avoid future misuse of the variable.

[Ben Goodger (Google), 2009-03-08 00:36:05]

OK with the nits fixed.

http://codereview.chromium.org/39313/diff/7/1011
File chrome/browser/views/password_manager_view.cc (right):

http://codereview.chromium.org/39313/diff/7/1011#newcode187
Line 187: row_count_observer_ = observer;
should be unix_hacker style and live in the header.

http://codereview.chromium.org/39313/diff/7/1012
File chrome/browser/views/password_manager_view.h (right):

http://codereview.chromium.org/39313/diff/7/1012#newcode24
Line 24: class PasswordManagerTableModelObserver {
FWIW I find the observer nomenclature here a bit confusing since it's not a
1-many relationship, in reality this is implemented by the container view of the
password manager table model. You might at least spell that out in the comment
here.

[Alpha Left Google, 2009-03-09 18:27:04]

On 2009/03/08 00:36:05, Ben Goodger wrote:
> OK with the nits fixed.
> 
> http://codereview.chromium.org/39313/diff/7/1011
> File chrome/browser/views/password_manager_view.cc (right):
> 
> http://codereview.chromium.org/39313/diff/7/1011#newcode187
> Line 187: row_count_observer_ = observer;
> should be unix_hacker style and live in the header.

Done.

> 
> http://codereview.chromium.org/39313/diff/7/1012
> File chrome/browser/views/password_manager_view.h (right):
> 
> http://codereview.chromium.org/39313/diff/7/1012#newcode24
> Line 24: class PasswordManagerTableModelObserver {
> FWIW I find the observer nomenclature here a bit confusing since it's not a
> 1-many relationship, in reality this is implemented by the container view of
the
> password manager table model. You might at least spell that out in the comment
> here.

It actually is a 1-many relationship. PasswordManagerView and
PasswordManagerExceptionsView are both PasswordManagerTableModelObserver, these
two classes have no relation.

[Ben Goodger (Google), 2009-03-09 19:15:56]

OK