[Intl] Integrated ICU data into Intl component
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
updated CHANGELOG for 2.5.5
updated VERSION for 2.5.5
bumped Symfony version to 2.5.6
[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
----------

[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
-------

e3dacbd [EventDispatcher] fix doc bloc on EventDispatcherInterface
bug #11920 [Intl] Integrated ICU data into Intl component #1 (webmozart)

This PR was merged into the 2.3 branch.

Discussion
----------

[Intl] Integrated ICU data into Intl component #1

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #11447, #10807
| License       | MIT
| Doc PR        | -

This PR is an alternative implementation to #11884. It depends on ~~#11906~~ and ~~#11907~~ being merged first (~~these are included in the diff until after a merge+rebase~~ merged+rebased now).

With this PR, the ICU component becomes obsolete. The ICU data is bundled with Intl in two different formats: JSON and the binary ICU resource bundle format (version 2) readable by PHP's `\ResourceBundle` class. For a performance comparison between the two, see my [benchmark](/webmozart/json-res-benchmark).

~~The data is contained in two zip files: json.zip (2.6MB) and rb-v2.zip (3.8MB). The handler~~

```php
\Symfony\Component\Intl\Composer\ScriptHandler::decompressData()
```

~~needs to be added as Composer hook and decompresses the data after install/update.~~

The data is included as text/binary now. Git takes care of the compression.

Before this PR can be merged, I would like to find out what the performance difference between the two formats is in real applications. For that, I need benchmarks from some real-life applications which use ICU data - e.g. in forms (language drop-downs, country selectors etc.) - for both the JSON and the binary data. You can force either format to be used by hard-coding the return value of `Intl::detectDataFormat()` to `Intl::JSON` and `Intl::RB_V2` respectively. I'll also try to create some more realistic benchmarks.

If JSON is not significantly slower/takes up significantly more memory than the binary format, we can drop the binary format altogether.

Commits
-------

be819c1 [Intl] Integrated ICU data into Intl component
[Intl] Generated the data for ICU version 54-rc
bug #11998 [Intl] Integrated ICU data into Intl component #2 (webmozart)

This PR was submitted for the master branch but it was merged into the 2.3 branch instead (closes #11998).

Discussion
----------

[Intl] Integrated ICU data into Intl component #2

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

Follow-up PR to #11920. This PR contains generated data files only.

Commits
-------

65a8b9f [Intl] Generated the data for ICU version 54-rc
[Intl] FIxed failing test
fix components tests

Since #12006, the `ContainerBuilder` contains the
`addExpressionLanguageProvider()` method which references a class from
the ExpressionLanguage component. By default, the PHPUnit mock API
tries to mock all methods of the class being doubled. Since the
ExpressionLanguage component is not required to run the tests,
creating the mock objects fails when the mock API fails to mock
the `addExpressionLanguageProvider()` method.
[Security][Http][Authentication] Make a test pass on HHVM
minor #12086 [Security][Http][Authentication] Make a test pass on HHVM (AlphaStream)

This PR was submitted for the master branch but it was merged into the 2.5 branch instead (closes #12086).

Discussion
----------

[Security][Http][Authentication] Make a test pass on HHVM

The test mocks AuthenticationException mocking all its (and its ancestors') methods. In HHVM's implementation of \Exception, a static method is called upon instantiation. Mock object generator, however, mocks static methods with 'throw' statements. All of these cause the SimpleAuthenticationHandlerTest to fail on HHVM when attempting to instantiate the mock.

The solution is to disable method mocking for AuthenticationException. An instance of this class is merely passed around between the authentication handler and the failure handler, and no methods are invoked on it. Hence, disabling method mocking should not weaken the unit test.

| 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
-------

7ff903e [Security][Http][Authentication] Make a test pass on HHVM
fixed CS