servo: Merge #12782 - WR2 does not require the stencil buffer, so remove it from window pro… (from glennw:wr-stencil); r=pcwalton,emilio

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- [ ] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

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…perties.

Source-Repo: https://github.com/servo/servo
Source-Revision: 2d54a2c30a5f7cb8a32eac561747582f47214e14

servo/ports/glutin/window.rs

@@ -157,10 +157,6 @@ impl Window {
             builder = builder.with_vsync();
         }
 
-        if opts::get().use_webrender {
-            builder = builder.with_stencil_buffer(8);
-        }
-
         if opts::get().use_msaa {
             builder = builder.with_multisampling(MULTISAMPLES)
         }