Auto merge of #9070 - antrik:debug-fonts, r=nox

Derive Debug for more font-related types

Needs to pull in newer ipc-channel and azure.

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components/gfx/font_cache_task.rs

@@ -80,7 +80,7 @@ impl FontTemplates {
 }
 
 /// Commands that the FontContext sends to the font cache task.
-#[derive(Deserialize, Serialize)]
+#[derive(Deserialize, Serialize, Debug)]
 pub enum Command {
     GetFontTemplate(FontFamily, FontTemplateDescriptor, IpcSender<Reply>),
     GetLastResortFontTemplate(FontTemplateDescriptor, IpcSender<Reply>),
@@ -90,7 +90,7 @@ pub enum Command {
 }
 
 /// Reply messages sent from the font cache task to the FontContext caller.
-#[derive(Deserialize, Serialize)]
+#[derive(Deserialize, Serialize, Debug)]
 pub enum Reply {
     GetFontTemplateReply(Option<Arc<FontTemplateData>>),
 }
@@ -315,7 +315,7 @@ impl FontCache {
 
 /// The public interface to the font cache task, used exclusively by
 /// the per-thread/task FontContext structures.
-#[derive(Clone, Deserialize, Serialize)]
+#[derive(Clone, Deserialize, Serialize, Debug)]
 pub struct FontCacheTask {
     chan: IpcSender<Command>,
 }

components/gfx/font_context.rs

@@ -44,17 +44,20 @@ fn create_scaled_font(template: &Arc<FontTemplateData>, pt_size: Au) -> ScaledFo
 
 static SMALL_CAPS_SCALE_FACTOR: f32 = 0.8;      // Matches FireFox (see gfxFont.h)
 
+#[derive(Debug)]
 struct LayoutFontCacheEntry {
     family: String,
     font: Option<Rc<RefCell<Font>>>,
 }
 
+#[derive(Debug)]
 struct FallbackFontCacheEntry {
     font: Rc<RefCell<Font>>,
 }
 
 /// A cached azure font (per paint task) that
 /// can be shared by multiple text runs.
+#[derive(Debug)]
 struct PaintFontCacheEntry {
     pt_size: Au,
     identifier: Atom,
@@ -69,6 +72,7 @@ static FONT_CACHE_EPOCH: AtomicUsize = ATOMIC_USIZE_INIT;
 /// working with fonts. It is the public API used by the layout and
 /// paint code. It talks directly to the font cache task where
 /// required.
+#[derive(Debug)]
 pub struct FontContext {
     platform_handle: FontContextHandle,
     font_cache_task: FontCacheTask,
@@ -316,6 +320,7 @@ impl HeapSizeOf for FontContext {
     }
 }
 
+#[derive(Debug)]
 struct LayoutFontGroupCacheKey {
     pointer: Arc<SpecifiedFontStyle>,
     size: Au,