implement wlr-gamma-control-unstable-v1

src/it/test_backend.rs

@@ -153,6 +153,7 @@ impl TestBackend {
                 format: XRGB8888,
                 color_space: Default::default(),
                 eotf: Default::default(),
+                gamma_lut: Default::default(),
             },
         };
         Self {

src/it/tests/t0034_workspace_restoration.rs

@@ -66,6 +66,7 @@ async fn test(run: Rc<TestRun>) -> TestResult {
             format: XRGB8888,
             color_space: Default::default(),
             eotf: Default::default(),
+            gamma_lut: Default::default(),
         },
     };
     run.backend