all: remove traditional i3 titlebars, add corner rounding

src/it/test_gfx_api.rs

@@ -528,6 +528,8 @@ impl GfxFramebuffer for TestGfxFb {
                     GfxApiOpt::Sync => {}
                     GfxApiOpt::FillRect(f) => fill_rect(&f, staging),
                     GfxApiOpt::CopyTexture(c) => copy_texture(&c, staging)?,
+                    GfxApiOpt::RoundedFillRect(_) => {}
+                    GfxApiOpt::RoundedCopyTexture(_) => {}
                 }
             }
             copy_from_staging(staging);