Auto merge of #24123 - gterzian:redo_blob, r=jdm

Restructure Blob, structured serialization

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FIX #24052 and also address the "cloning" half of FIX #23917

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- [ ] These changes fix #___ (GitHub issue number if applicable)

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- [ ] These changes do not require tests because ___

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1 files changed, 38 insertions, 0 deletions

diff --git a/components/msg/constellation_msg.rs b/components/msg/constellation_msg.rs
index 1214b68aa29..f4e7a517673 100644
--- a/components/msg/constellation_msg.rs
+++ b/components/msg/constellation_msg.rs
@@ -170,6 +170,13 @@ impl PipelineNamespace {
             index: MessagePortRouterIndex(self.next_index()),
         }
     }
+
+    fn next_blob_id(&mut self) -> BlobId {
+        BlobId {
+            namespace_id: self.id,
+            index: BlobIndex(self.next_index()),
+        }
+    }
 }
 
 thread_local!(pub static PIPELINE_NAMESPACE: Cell<Option<PipelineNamespace>> = Cell::new(None));
@@ -374,6 +381,37 @@ impl fmt::Display for MessagePortRouterId {
 }
 
 #[derive(Clone, Copy, Debug, Deserialize, Eq, Hash, Ord, PartialEq, PartialOrd, Serialize)]
+pub struct BlobIndex(pub NonZeroU32);
+malloc_size_of_is_0!(BlobIndex);
+
+#[derive(
+    Clone, Copy, Debug, Deserialize, Eq, Hash, MallocSizeOf, Ord, PartialEq, PartialOrd, Serialize,
+)]
+pub struct BlobId {
+    pub namespace_id: PipelineNamespaceId,
+    pub index: BlobIndex,
+}
+
+impl BlobId {
+    pub fn new() -> BlobId {
+        PIPELINE_NAMESPACE.with(|tls| {
+            let mut namespace = tls.get().expect("No namespace set for this thread!");
+            let next_blob_id = namespace.next_blob_id();
+            tls.set(Some(namespace));
+            next_blob_id
+        })
+    }
+}
+
+impl fmt::Display for BlobId {
+    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
+        let PipelineNamespaceId(namespace_id) = self.namespace_id;
+        let BlobIndex(index) = self.index;
+        write!(fmt, "({},{})", namespace_id, index.get())
+    }
+}
+
+#[derive(Clone, Copy, Debug, Deserialize, Eq, Hash, Ord, PartialEq, PartialOrd, Serialize)]
 pub struct HistoryStateIndex(pub NonZeroU32);
 malloc_size_of_is_0!(HistoryStateIndex);