Auto merge of #21688 - paulrouget:rm-clipboard, r=jdm

Let the clipboard crate handle the lack of clipboard support

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- [ ] These changes fix #__ (github issue number if applicable).

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components/servo/lib.rs

@@ -151,7 +151,6 @@ where
             create_compositor_channel(window.create_event_loop_waker());
         let (embedder_proxy, embedder_receiver) =
             create_embedder_channel(window.create_event_loop_waker());
-        let supports_clipboard = window.supports_clipboard();
         let time_profiler_chan = profile_time::Profiler::create(
             &opts.time_profiling,
             opts.time_profiler_trace_path.clone(),
@@ -221,7 +220,6 @@ where
             mem_profiler_chan.clone(),
             debugger_chan,
             devtools_chan,
-            supports_clipboard,
             &mut webrender,
             webrender_document,
             webrender_api_sender,
@@ -493,7 +491,6 @@ fn create_constellation(
     mem_profiler_chan: mem::ProfilerChan,
     debugger_chan: Option<debugger::Sender>,
     devtools_chan: Option<Sender<devtools_traits::DevtoolsControlMsg>>,
-    supports_clipboard: bool,
     webrender: &mut webrender::Renderer,
     webrender_document: webrender_api::DocumentId,
     webrender_api_sender: webrender_api::RenderApiSender,
@@ -569,7 +566,6 @@ fn create_constellation(
         private_resource_threads,
         time_profiler_chan,
         mem_profiler_chan,
-        supports_clipboard,
         webrender_document,
         webrender_api_sender,
         webgl_threads,