Resolve unknown generic type to bound instead of ErrorType

Author: ondrejmirtes

src/Reflection/ClassReflection.php

@@ -897,7 +897,7 @@ public function typeMapToList(TemplateTypeMap $typeMap): array
 
 		$list = [];
 		foreach ($resolvedPhpDoc->getTemplateTags() as $tag) {
-			$list[] = $typeMap->getType($tag->getName()) ?? new ErrorType();
+			$list[] = $typeMap->getType($tag->getName()) ?? $tag->getBound();
 		}
 
 		return $list;

tests/PHPStan/Analyser/data/generics.php

@@ -883,7 +883,7 @@ function cache1($t): void {
 function newHandling(): void {
 	assertType('PHPStan\Generics\FunctionsAssertType\C<mixed>', new C());
 	assertType('PHPStan\Generics\FunctionsAssertType\A<stdClass>', new A(new \stdClass()));
-	assertType('PHPStan\Generics\FunctionsAssertType\A<*ERROR*>', new A());
+	assertType('PHPStan\Generics\FunctionsAssertType\A<mixed>', new A());
 }
 
 /**