Auto merge of #18096 - glennw:update-wr-deinit, r=jdm

Update WR (new texture cache allocator, shader deinit path).

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ports/servo/main.rs

@@ -183,6 +183,8 @@ fn main() {
 
     unregister_glutin_resize_handler(&window);
 
+    servo_wrapper.servo.deinit();
+
     platform::deinit()
 }