[2.6] Remove possible call_user_func()
[2.3] Remove possible call_user_func()
[2.5] Remove possible call_user_func()
Fixed #12845 adding a listener to an event that is currently being dispatched will not result into a fatal error in TraceableEventDispatcher [EventDispatcher]
[DependencyInjection] backport perf optim

Conflicts:
	src/Symfony/Component/DependencyInjection/Dumper/PhpDumper.php
	src/Symfony/Component/DependencyInjection/Tests/Fixtures/php/services11.php
	src/Symfony/Component/DependencyInjection/Tests/Fixtures/php/services19.php
	src/Symfony/Component/DependencyInjection/Tests/Fixtures/php/services9.php
	src/Symfony/Component/DependencyInjection/Tests/Fixtures/php/services9_compiled.php
[DependencyInjection] perf optim: call dirname() at most 5x
[ClassLoader] Fix undefined index in ClassCollectionLoader
Minor phpcs fixes
minor #12886 Minor phpcs fixes (acrobat)

This PR was merged into the 2.3 branch.

Discussion
----------

Minor phpcs fixes

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

Small phpcs fixes

Commits
-------

9a0d5c3 Minor phpcs fixes
[2.6] CS Fixes And Removed An Unused Import
minor #12872 [2.6] CS Fixes And Removed An Unused Import (GrahamCampbell)

This PR was squashed before being merged into the 2.6 branch (closes #12872).

Discussion
----------

[2.6] CS Fixes And Removed An Unused Import

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

##### This pull request fixes some cs issues in symfony 2.6.

This is the sequel to #12856.

Commits
-------

2f10a0a [2.6] CS Fixes And Removed An Unused Import
fix phpdoc's alignment
minor #12887 [2.3] CS Fixes: fix phpdoc's alignment (keradus)

This PR was merged into the 2.3 branch.

Discussion
----------

[2.3] CS Fixes: fix phpdoc's alignment

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

Fix phpdoc's alignment

Commits
-------

f588610 fix phpdoc's alignment
bug #12858 [ClassLoader] Fix undefined index in ClassCollectionLoader (szicsu)

This PR was merged into the 2.3 branch.

Discussion
----------

[ClassLoader] Fix undefined index in ClassCollectionLoader

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

Commits
-------

cfdb925 [ClassLoader] Fix undefined index in ClassCollectionLoader
[Console] fixes some typos and phpdoc.
Adding note about the PdoSessionHandler BC break
Adding note about known BC issues
minor #12884 [Console] fixes some typos and phpdoc. (hhamon)

This PR was merged into the 2.5 branch.

Discussion
----------

[Console] fixes some typos and phpdoc.

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

Commits
-------

86840df [Console] fixes some typos and phpdoc.
Added information when an error occured during validation of an answer of a question
bug #12806 [Console] Removed the use of $this->getHelperSet() as it is null by default (saro0h)

This PR was submitted for the 2.6 branch but it was merged into the 2.5 branch instead (closes #12806).

Discussion
----------

[Console] Removed the use of $this->getHelperSet() as it is null by default

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #12805
| License       | MIT
| Doc PR        | ~

Before:
![capture d ecran 2014-12-02 a 15 51 38](https://cloud.githubusercontent.com/assets/667519/5264798/303bf87a-7a3e-11e4-9b45-68e8a86bab60.png)

After:
![capture d ecran 2014-12-02 a 16 36 25](https://cloud.githubusercontent.com/assets/667519/5265299/b13190d6-7a41-11e4-9e68-d889ea290cae.png)

Commits
-------

111b194 Added information when an error occured during validation of an answer of a question