Skip FailedStorage in background scan

* Skip null groups in group manager (#26871)

* Skip null groups in group manager

* Also skip null groups in group manager's search function

* Add more group null checks in sharing code

* Add unit tests for null group safety in group manager

* Add unit tests for sharing code null group checks

* Added tests for null groups handling in sharing code

* Ignore moveShare optional repair in mount provider

In some cases, data is inconsistent in the oc_share table due to legacy
data. The mount provider might attempt to make it consistent but if the
target group does not exist any more it cannot work. In such case we
simply ignore the exception as it is not critical. Keeping the
exception would break user accounts as they would be unable to use
their filesystem.

* Adjust null group handing + tests

* Fix new group manager tests

On the login screen a warning will pop up if an unsupported/outdated browser is used

Integration test encryption homedir

Ignore exception when deleting keys of deleted user

Whenever a user was deleted for encryption where the keys are stored in
the home, we can ignore user existence exceptions because it means the
keys are already gone.

This reverts commit 4559dad3e421f330eb8cbc718aa19e573a5ae2f7.

Added filter to disable some tests when encryption is enabled.

* Handle reading non-existing characters for any depth

* Refactor imagecreatefrombmp

* Fix undefined variable. Use class constant

* Increase coverage

Update version in master to 10.0.0.X #26866

Don't mount user home with alternate keys root

Backbone Webdav adapter MKCOL support

Usually Backbone collections cannot be created and just simply exists.
But in the Webdav world they need to be creatable.

This enhancement makes it possible to use a Backbone Model to represent
such collections and when creating it, it will use MKCOL instead of PUT.

Update doctrine/dbal to 2.5.7

Because we sometimes need to mount the user's home before deleting
encryption keys, this must happen in a preDelete hook because the
postDelete is too late. In postDelete the user's home already doesn't
exist any more and cannot be mounted.

* Prevent PHP request to get killed when using fclose callback

* Add ignore_user_abort everywhere where the time limit is set to 0

When encryption keys are stored outside the user's homes, there is no
need to mount said homes.

* The file system of a user has to be properly setup before accessing the keys

* Fix unit test execution

* Init mount points for user in more places in Keys\Storage

* Fix encryption key storage tests to properly create required users

* Added test that check if user home is mounted after resolving key

* remove obsolete hack

> // file_get_contents() has a memory leak: https://bugs.php.net/bug.php?id=61961
was closed 4 years ago. we could also use the Common implementation

* jeeez

Integration tests fixing alt home

Merge pull request #26915 from owncloud/integration-tests-adding-provisioningapi-v2-support-to-sharees

Added tests for sharees using v2.php