Enable legacy feature where needed in subxt_metadata so it compiles on its own

Author: jsdw

.github/workflows/rust.yml

@@ -188,6 +188,7 @@ jobs:
       - name: Cargo hack; check each subxt feature
         run: cargo hack -p subxt --each-feature check --exclude-no-default-features --exclude-all-features --exclude-features web --features native
 
+      # Same with subxt-historic
       - name: Cargo hack; check each subxt feature
         run: cargo hack -p subxt-historic --each-feature check --exclude-no-default-features --exclude-all-features --exclude-features web --features native
 

metadata/Cargo.toml

@@ -18,7 +18,12 @@ default = ["std", "legacy"]
 std = ["scale-info/std", "frame-metadata/std"]
 
 # Enable decoding of legacy metadata, too.
-legacy = ["dep:scale-info-legacy", "dep:scale-type-resolver"]
+legacy = [
+    "dep:scale-info-legacy", 
+    "dep:scale-type-resolver",
+    "frame-decode/legacy",
+    "frame-metadata/legacy"
+]
 
 [dependencies]
 scale-info = { workspace = true, default-features = false }