feature #18726 [PhpUnitBridge] Make ClockMock match namespaces that begin with Tests\\ (teohhanhui)

This PR was submitted for the 2.8 branch but it was merged into the 3.2-dev branch instead (closes #18726).

Discussion
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[PhpUnitBridge] Make ClockMock match namespaces that begin with Tests\\

| Q             | A
| ------------- | ---
| Branch?       | 2.8
| Bug fix?      | yes?
| New feature?  | no
| BC breaks?    | no?
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | N/A
| License       | MIT
| Doc PR        | symfony/symfony-docs#6546

See symfony/symfony-standard#969

Commits
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2630c13 [PhpUnitBridge] Make ClockMock match namespaces that begin with Tests\\

src/Symfony/Bridge/PhpUnit/ClockMock.php

@@ -77,6 +77,8 @@ class ClockMock
         if (0 < strpos($class, '\\Tests\\')) {
             $ns = str_replace('\\Tests\\', '\\', $class);
             $mockedNs[] = substr($ns, 0, strrpos($ns, '\\'));
+        } elseif (0 === strpos($class, 'Tests\\')) {
+            $mockedNs[] = substr($class, 6, strrpos($class, '\\') - 6);
         }
         foreach ($mockedNs as $ns) {
             if (function_exists($ns.'\time')) {