Auto merge of #22028 - asajeffrey:debug-all-the-things, r=emilio

Add lots of derived Debug impls

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Add a bunch of derived `Debug` impls. After this, pretty much anything that implements `Deserializable` also implements `Debug`. The exception is `webrender_api::RenderApiSender`, which would need a webrender PR.

---
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes do not require tests because it's just debugging

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components/gfx/text/text_run.rs

@@ -23,7 +23,7 @@ thread_local! {
 }
 
 /// A single "paragraph" of text in one font size and style.
-#[derive(Clone, Deserialize, Serialize)]
+#[derive(Clone, Debug, Deserialize, Serialize)]
 pub struct TextRun {
     /// The UTF-8 string represented by this text run.
     pub text: Arc<String>,
@@ -51,7 +51,7 @@ impl Drop for TextRun {
 }
 
 /// A single series of glyphs within a text run.
-#[derive(Clone, Deserialize, Serialize)]
+#[derive(Clone, Debug, Deserialize, Serialize)]
 pub struct GlyphRun {
     /// The glyphs.
     pub glyph_store: Arc<GlyphStore>,