servo: Merge #17905 - Issue 17882: Remove rendering_threads option in the CEF port (from abahmed:update_CEF_port); r=emilio

Fixes issue 17882 by removing rendering_threads option in the CEF port
r?@highfive

---
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Source-Repo: https://github.com/servo/servo
Source-Revision: c329e640f07c3f22caa496679f9afaa4e762cc75

--HG--
extra : subtree_source : https%3A//hg.mozilla.org/projects/converted-servo-linear
extra : subtree_revision : 59ca85ea3389bb7fa3ab4f01f6292be20de4de09

servo/ports/cef/types.rs

@@ -727,11 +727,6 @@ pub struct cef_settings {
   // of the background color but will be otherwise ignored.
   //
   pub background_color: cef_color_t,
-
-  //
-  // Determines how many rendering threads are used.
-  //
-  pub rendering_threads: c_int,
 }
 
 //