Fix concurrent request when updating build log in browser
If you have a slow internet connection the trace will not be updated correctly. We need to check if our request is the latest one.
Fixes: https://gitlab.com/gitlab-org/gitlab-ce/issues/17535
See merge request !4183
Fixed issue with enter key selecting wrong option in dropdown
If you search for a label and press enter the dropdown will select the last element rather than the first. This is because the currentIndex is -1 rather than 0

Closes#17630
See merge request !4210
Fixed issue with merge button color

Closes#17644
See merge request !4211
Fix Error 500 in CI charts by gracefully handling commits with no durations
## What does this MR do?
In the CI charts, this MR reports the duration of a commit to 0 if it is `nil`.
## Are there points in the code the reviewer needs to double check?
Should we omit this commit from the chart or set it to some other value?
## Why was this MR needed?
We were getting an Error 500 here: https://gitlab.com/gitlab-org/gitlab-ce/graphs/master/ci
## What are the relevant issue numbers?
#17730
See merge request !4245
Fix Error 500 when accessing application settings due to nil disabled OAuth sign-in sources
## What does this MR do?
When upgrading to GitLab 8.8, an admin would encounter an Error 500 due to a `nil` `disabled_oauth_sign_in_sources`. This MR ensures that the value will be a blank array if empty.
Closes#17564
See merge request !4242
Allow anonymous user to access pipelines
## What does this MR do?
It fixes an issue where the Pipelines is shown for the Anonymous users,
but they get 404 when clicked. Their session is then logged out.
Fixes#17717.
See merge request !4233
Added remove due date button
In the sidebar when there is a due date a link to remove due date becomes visible

Closes#17392
See merge request !4209
Allow anonymous user to access pipelines
## What does this MR do?
It fixes an issue where the Pipelines is shown for the Anonymous users,
but they get 404 when clicked. Their session is then logged out.
Fixes#17717.
See merge request !4233
Fix the CI login to Container Registry (the gitlab-ci-token user)
## What does this MR do?
This fixes `docker login` not succeeding when trying to do CI login: `gitlab-ci-token with $CI_BUILD_TOKEN`.
cc @marin
See merge request !4236
Allows MR authors to have the source branch removed when merging the MR
closes#13191
The location of the checkbox might not be optimal so any feedback is welcome. Any other feedback too obviously.
Screenshot:

See merge request !2801
Update CE code to include some refactor done in EE to do with import url
This is simply updating the code to match EE and avoid further conflicts related to `import_data` and `import_url` changes made on EE only.
See merge request !4223
Create a todo on failing MR build
Implements #14067. I worked on this with @DouweM (any mistakes are mine).
When a build fails for a commit, create a todo for the author of the merge request that commit is the HEAD of. If the commit isn't the HEAD commit of any MR, don't do anything. If there already is a todo for that user and MR, don't do anything.
Current limitations:
- This isn't configurable by project.
- The author of a merge request might not be the person who pushed the breaking commit.
- I haven't tested this with a working CI setup, just with the unit tests below and by modifying my DB directly.
See merge request !3177