Deprecate methods for configuring no longer configurable features

In 3.0.0, it is no longer possible to disable lazy ghost objects, and
likewise, it is no longer possible to disable rejecting id collisions in
the identity map, so let us deprecate the related methods.
I was supposed to do this in 3.1.0.

Author: greg0ire

UPGRADE.md

@@ -1,3 +1,16 @@
+# Upgrade to 3.5
+
+## Deprecate methods for configuring no longer configurable features
+
+Since 3.0, lazy ghosts are enabled unconditionally, and so is rejecting ID
+collisions in the identity map.
+
+As a consequence, the following methods are deprecated and will be removed in 4.0:
+* `Doctrine\ORM\Configuration::setLazyGhostObjectEnabled()`
+* `Doctrine\ORM\Configuration::isLazyGhostObjectEnabled()`
+* `Doctrine\ORM\Configuration::setRejectIdCollisionInIdentityMap()`
+* `Doctrine\ORM\Configuration::isRejectIdCollisionInIdentityMapEnabled()`
+
 # Upgrade to 3.4
 
 ## Discriminator Map class duplicates
@@ -26,7 +39,7 @@ The class `Doctrine\ORM\Mapping\Driver\DatabaseDriver` is deprecated without rep
 
 Output walkers should implement the new `\Doctrine\ORM\Query\OutputWalker` interface and create
 `Doctrine\ORM\Query\Exec\SqlFinalizer` instances instead of `Doctrine\ORM\Query\Exec\AbstractSqlExecutor`s.
-The output walker must not base its workings on the query `firstResult`/`maxResult` values, so that the 
+The output walker must not base its workings on the query `firstResult`/`maxResult` values, so that the
 `SqlFinalizer` can be kept in the query cache and used regardless of the actual `firstResult`/`maxResult` values.
 Any operation dependent on `firstResult`/`maxResult` should take place within the `SqlFinalizer::createExecutor()`
 method. Details can be found at https://github.com/doctrine/orm/pull/11188.

src/Configuration.php

@@ -610,7 +610,7 @@ public function enableNativeLazyObjects(bool $nativeLazyObjects): void
     }
 
     /**
-     * To be deprecated in 3.1.0
+     * @deprecated lazy ghost objects are always enabled
      *
      * @return true
      */
@@ -619,7 +619,7 @@ public function isLazyGhostObjectEnabled(): bool
         return true;
     }
 
-    /** To be deprecated in 3.1.0 */
+    /** @deprecated lazy ghost objects cannot be disabled */
     public function setLazyGhostObjectEnabled(bool $flag): void
     {
         if (! $flag) {
@@ -630,7 +630,7 @@ public function setLazyGhostObjectEnabled(bool $flag): void
         }
     }
 
-    /** To be deprecated in 3.1.0 */
+    /** @deprecated rejecting ID collisions in the identity map cannot be disabled */
     public function setRejectIdCollisionInIdentityMap(bool $flag): void
     {
         if (! $flag) {
@@ -642,7 +642,7 @@ public function setRejectIdCollisionInIdentityMap(bool $flag): void
     }
 
     /**
-     * To be deprecated in 3.1.0
+     * @deprecated rejecting ID collisions in the identity map is always enabled
      *
      * @return true
      */