Make Doctrine's dependency injection test less fragile.

[Doctrine][DependencyInjection] The test checks that a few items are ordered according to the value of their 'priority' attribute. However, a few of the items have the same value of this attribute. RegisterEventListenersAndSubscribersPass doesn't use a stable sorting, yet the test asserts that items that are 'equal' shall go in the original order. Modified so that the order of the original items is not checked.
minor #12058 [Doctrine][DependencyInjection] Make a test less fragile. (AlphaStream)

This PR was submitted for the master branch but it was merged into the 2.3 branch instead (closes #12058).

Discussion
----------

[Doctrine][DependencyInjection] Make a test less fragile.

The test checks that a few items are ordered according to the value of their 'priority' attribute. However, a few of the items have the same value of this attribute. RegisterEventListenersAndSubscribersPass doesn't use a stable sorting, yet the test asserts that items that are 'equal' shall go in the original order. Modified so that the order of the original items is not checked.

| Q             | A
| ------------- | ---
| Bug fix?      | [no]
| New feature?  | [no]
| BC breaks?    | [no]
| Deprecations? | [no]
| Tests pass?   | [yes]
| Fixed tickets | [none]
| License       | MIT
| Doc PR        | [none]

Commits
-------

f1ae970 Make Doctrine's dependency injection test less fragile.
[SecurityBundle] fixed tests when used in standalone
updated CHANGELOG for 2.3.20
update CONTRIBUTORS for 2.3.20
updated VERSION for 2.3.20
bumped Symfony version to 2.3.21
[Validator] Update validators.zh_CN.xlf, fix translation error
minor #12070 [Validator] Update validators.zh_CN.xlf, fix translation error (michaeljayt)

This PR was submitted for the master branch but it was merged into the 2.3 branch instead (closes #12070).

Discussion
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[Validator] Update validators.zh_CN.xlf, fix translation error

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets |
| License       | MIT
| Doc PR        |

Commits
-------

ab5aaab [Validator] Update validators.zh_CN.xlf, fix translation error
[EventDispatcher] fix doc bloc on EventDispatcherInterface
minor #12080 [EventDispatcher] fix doc bloc on EventDispatcherInterface (nicolas-grekas)

This PR was merged into the 2.3 branch.

Discussion
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[EventDispatcher] fix doc bloc on EventDispatcherInterface

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | -
| License       | MIT
| Doc PR        | -

The doc block says that an array of event names is accepted as input, but no implementation is compliant with that description.

Commits
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e3dacbd [EventDispatcher] fix doc bloc on EventDispatcherInterface