Config static cache is not cleared properly on rename

I could not find any flaws, except for nitpicks. Looks ready to me.

1. +++ b/core/modules/config/src/Tests/ConfigCRUDTest.php
   @@ -117,13 +117,26 @@ function testCRUD() {
   +    // Pollute the non overrides static cache.
   ...
   +    // Ensure the non overrides static cache has been cleared.
   

   s/non overrides/non-overrides/

2. +++ b/core/modules/config/src/Tests/ConfigCRUDTest.php
   @@ -117,13 +117,26 @@ function testCRUD() {
   +    $config_factory->setOverrideState(TRUE);
   

   Could use a symmetrical comment, like "Restore overrides".

3. +++ b/core/modules/config/src/Tests/ConfigCRUDTest.php
   @@ -117,13 +117,26 @@ function testCRUD() {
        $new_name = 'config_test.crud_rename_no_cache';
   

   Could perhaps using a comment above it, to indicate that this is where the *actual* renaming happens, and the testing of that?

Critical due to #2392319-19: Config objects (but not config entities) should by default be immutable by @alexpott.

Agreed with Wim, looks good. One more nit:

+++ b/core/modules/config/src/Tests/ConfigCRUDTest.php
@@ -117,13 +117,26 @@ function testCRUD() {
+    // Remove overrides.

Turn off overrides? (We don't actually remove them).

Patch with those suggestions applied.

Looks great :)

Committed/pushed to 8.0.x, thanks!