different number of updates in wp-admin

[Kniebremser]

In my test environment I may have found a bug in the display of the number of updates.

Test computer: Win 8.1 and XAMMP and Firefox 30 Beta 3

Steps to reproduce:
1 WordPress 4.0 is updated.
2 calls wp-admin -> dashboard -> update on
3 Delete the plugin Askimet via windows explorer
4 load wp-admin -> dashboard -> update again with firefox

In wp-admin-bar I see the number "0"
in wp-admin -> dashboard -> updates i see the number "1"

I click on wp-admin -> dashboard -> updates, then change the value to 0

[SergeyBiryukov]

Duplicate of #18098.