[HttpKernel] changed fragment URLs to be relative by default (closes #8458)
optimized circular reference checker
merged branch tgabi333/master (PR #8891)

This PR was submitted for the master branch but it was merged into the 2.2 branch instead (closes #8891).

Discussion
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[DependencyInjection] optimized circular reference checker

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

It is an addtion to my previous PR https://github.com/symfony/symfony/pull/7699

There is no need to check again previously checked sub-trees.

In our tightly coupled services graph, this circular reference check runs avg 1,5ms, before that: 100ms

Commits
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67ebf8f optimized circular reference checker
Fixed PHPDoc Blocks

These ```RunTimeExceptions``` are NOT the native ones, therefor the should not be ```\``` in front of them.
merged branch ChristianGaertner/patch-1 (PR #8887)

This PR was submitted for the master branch but it was merged into the 2.2 branch instead (closes #8887).

Discussion
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[Process] Fixed PHPDoc Blocks

These ```RunTimeExceptions``` are NOT the native ones, therefor the should not be ```\``` in front of them.

| Q             | A
| ------------- | ---
| Fixed tickets | none
| License       | MIT

Commits
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26e9717 Fixed PHPDoc Blocks
merged branch fabpot/fragment-urls (PR #8879)

This PR was merged into the 2.2 branch.

Discussion
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Made fragment URLs relative instead of absolute by default

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #8458
| License       | MIT
| Doc PR        | n/a

This fixes a regression introduced with the new fragment system where fragment URLs were generated as absolute URLs. As per the ESI spec, there is no need to generate an absolute URL and this can even be problematic when dealing with internal sub-requests in a more "complex" hosting environment.

Commits
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91234cd [HttpKernel] changed fragment URLs to be relative by default (closes #8458)