Fix "absolute path" when we look to the cache directory

We should get __DIR__ instead of __DIR__ . '/.'
bug #10937 [HttpKernel] Fix "absolute path" when we look to the cache directory (BenoitLeveque)

This PR was submitted for the master branch but it was merged into the 2.3 branch instead (closes #10937).

Discussion
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[HttpKernel] Fix "absolute path" when we look to the cache directory

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

We should get ``__DIR__`` instead of ``__DIR__ . '/.'``

I've seen this issue when trying to play with the symfony standard new directory structure

Commits
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4735e56 Fix "absolute path" when we look to the cache directory
fixed CS
Fixed the Travis build to avoid exiting too early
minor #10950 Fixed the Travis build to avoid exiting too early (stof)

This PR was squashed before being merged into the 2.3 branch (closes #10950).

Discussion
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Fixed the Travis build to avoid exiting too early

currently, failed tests on Travis are exiting the build too early, avoiding to run some tests and maybe even loosing some output. See https://github.com/travis-ci/travis-ci/issues/2346 for more details

Commits
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2e64fb1 Fixed the Travis build to avoid exiting too early
Fixed test cases failing when the Intl extension is not installed
minor #10955 Fixed test cases failing when the Intl extension is not installed (webmozart)

This PR was merged into the 2.3 branch.

Discussion
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Fixed test cases failing when the Intl extension is not installed

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

I tested the 2.3 branch against PHP 5.5.12 with the following ICU versions:

* none
* 4.0
* 4.2
* 4.4
* 4.6
* 4.8
* 49
* 50
* 51
* 52
* 53

This PR contains the related fixes.

Commits
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fad38e8 Fixed test cases failing when the Intl extension is not installed
[HttpKernel] fixed file uploads in functional tests when no file was selected

Allow user to submit a form with no file selected.
bug #10953 [HttpKernel] fixed file uploads in functional tests without file selected (realmfoo)

This PR was submitted for the master branch but it was merged into the 2.3 branch instead (closes #10953).

Discussion
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[HttpKernel] fixed file uploads in functional tests without file selected

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

Commits
-------

6f56d87 [HttpKernel] fixed file uploads in functional tests when no file was selected
[DomCrawler] Added more tests for the XPath filtering

This will ensure we don't introduce regressions again when fixing #10206.
[DomCrawler] Fixed filterXPath() chaining
Fixed the XPath filtering to have the same behavior than Symfony 2.4