Fix TraceableSerializer when collected caller from array map

If the TraceableSerializer runs from a callable in an array_map, then
the caller looses the file and the line because it was invoked. This
causes a hard fail since the required items are not defined. The error
is the following:
TraceableSerializer.php line 174:
Warning: Undefined array key "file".

The fix is to get the file and the line from the following array item
which always is the caller class.

Author: OrestisZag

src/Symfony/Component/Serializer/Debug/TraceableSerializer.php

@@ -179,8 +179,8 @@ private function getCaller(string $method, string $interface): array
                 && $method === $trace[$i]['function']
                 && is_a($trace[$i]['class'], $interface, true)
             ) {
-                $file = $trace[$i]['file'];
-                $line = $trace[$i]['line'];
+                $file = $trace[$i]['file'] ?? $trace[$i + 1]['file'];
+                $line = $trace[$i]['line'] ?? $trace[$i + 1]['line'];
 
                 break;
             }

src/Symfony/Component/Serializer/Tests/Debug/TraceableSerializerTest.php

@@ -126,6 +126,40 @@ public function testAddDebugTraceIdInContext()
         $traceableSerializer->encode('data', 'format');
         $traceableSerializer->decode('data', 'format');
     }
+
+    public function testCollectedCaller()
+    {
+        $serializer = new \Symfony\Component\Serializer\Serializer();
+
+        $collector = new SerializerDataCollector();
+        $traceableSerializer = new TraceableSerializer($serializer, $collector);
+
+        $traceableSerializer->normalize('data');
+        $collector->lateCollect();
+
+        $this->assertSame([
+            'name' => 'TraceableSerializerTest.php',
+            'file' => __FILE__,
+            'line' => __LINE__ - 6,
+        ], $collector->getData()['normalize'][0]['caller']);
+    }
+
+    public function testCollectedCallerFromArrayMap()
+    {
+        $serializer = new \Symfony\Component\Serializer\Serializer();
+
+        $collector = new SerializerDataCollector();
+        $traceableSerializer = new TraceableSerializer($serializer, $collector);
+
+        array_map([$traceableSerializer, 'normalize'], ['data']);
+        $collector->lateCollect();
+
+        $this->assertSame([
+            'name' => 'TraceableSerializerTest.php',
+            'file' => __FILE__,
+            'line' => __LINE__ - 6,
+        ], $collector->getData()['normalize'][0]['caller']);
+    }
 }
 
 class Serializer implements SerializerInterface, NormalizerInterface, DenormalizerInterface, EncoderInterface, DecoderInterface