Merge branch '4.3' into 4.4

* 4.3:
  [Cache] fix memory leak when using PhpFilesAdapter
  [Yaml] Implement multiline string as scalar block for tagged values
  [HttpFoundation] Use `Cache-Control: must-revalidate` only if explicit lifetime has been given
  [FrameworkBundle] Use UserInterface to @return in getUser method
  [CI] Replace php7.4snapshot with php7.4 in Travis configuration
  [ExpressionLanguage][Node][BinaryNode] Process division by zero
  forward caught exception
  [Validator][ConstraintValidator] Stop passing unnecessary timezone argument to \DateTime
  add tags before processing them
  [MonologBridge] Fix debug processor datetime type

Author: nicolas-grekas

HttpCache/ResponseCacheStrategy.php

@@ -110,8 +110,6 @@ public function update(Response $response)
         $response->headers->set('Age', $this->age);
 
         if ($this->isNotCacheableResponseEmbedded) {
-            $response->setExpires($response->getDate());
-
             if ($this->flagDirectives['no-store']) {
                 $response->headers->set('Cache-Control', 'no-cache, no-store, must-revalidate');
             } else {

Tests/HttpCache/HttpCacheTest.php

@@ -1240,7 +1240,6 @@ public function testEsiCacheForceValidation()
         $this->request('GET', '/', [], [], true);
         $this->assertEquals('Hello World! My name is Bobby.', $this->response->getContent());
         $this->assertNull($this->response->getTtl());
-        $this->assertTrue($this->response->mustRevalidate());
         $this->assertTrue($this->response->headers->hasCacheControlDirective('private'));
         $this->assertTrue($this->response->headers->hasCacheControlDirective('no-cache'));
     }
@@ -1271,7 +1270,6 @@ public function testEsiCacheForceValidationForHeadRequests()
         // This can neither be cached nor revalidated, so it should be private/no cache
         $this->assertEmpty($this->response->getContent());
         $this->assertNull($this->response->getTtl());
-        $this->assertTrue($this->response->mustRevalidate());
         $this->assertTrue($this->response->headers->hasCacheControlDirective('private'));
         $this->assertTrue($this->response->headers->hasCacheControlDirective('no-cache'));
     }