Renamed `redacted_because_id` to `org.continuwuity.redacted_by` for proper namespacing; `get_unsigned_context` now lives in helpers.rs instead of `mod.rs`. The helper function also now explicitly wipes `unsigned` for `redacted_because` to avoid leaks (see comment).

@@ -18,0 +28,4 @@
+	/// This function panics if any value cannot be serialised, which should not
+	/// happen provided `membership`, `prev_content`, and `redacted_because` are
+	/// well-formed.
+	pub fn set_unsigned(

@@ -18,0 +27,4 @@
+	///
+	/// This function panics if any value cannot be serialised, which should not
+	/// happen provided `membership`, `prev_content`, and `redacted_because` are
+	/// well-formed.

@@ -24,1 +54,3 @@
-		use BTreeMap as Map;
+		if let Some(prev_content) = prev_content {
+			unsigned.insert("prev_content".to_owned(), to_raw_value(&prev_content)?);
+			// TODO(nex): prev_sender is still inserted in append.rs because

@@ -25,0 +60,4 @@
+			// proper solution, especially since every callsite has one
+		}
+		if let Some(redacted_because) = redacted_because {
+			unsigned.remove("org.continuwuity.redacted_by");

@@ -328,0 +372,4 @@
+						.user_can_see_event(
+							sender_user,
+							&event.room_id_or_hash(),
+							event.event_id(),