Cleanup: Replace use of _::StructReader in RPC interfaces with AnyStruct::Reader.

c++/src/capnp/rpc-prelude.h

@@ -61,7 +61,7 @@ public:
     virtual kj::Promise<void> shutdown() = 0;
     virtual AnyStruct::Reader baseGetPeerVatId() = 0;
   };
-  virtual kj::Maybe<kj::Own<Connection>> baseConnect(_::StructReader vatId) = 0;
+  virtual kj::Maybe<kj::Own<Connection>> baseConnect(AnyStruct::Reader vatId) = 0;
   virtual kj::Promise<kj::Own<Connection>> baseAccept() = 0;
 };
 
@@ -92,10 +92,8 @@ private:
   class Impl;
   kj::Own<Impl> impl;
 
-  Capability::Client baseBootstrap(_::StructReader vatId);
-  Capability::Client baseRestore(_::StructReader vatId, AnyPointer::Reader objectId);
-  // TODO(someday):  Maybe define a public API called `TypelessStruct` so we don't have to rely
-  // on `_::StructReader` here?
+  Capability::Client baseBootstrap(AnyStruct::Reader vatId);
+  Capability::Client baseRestore(AnyStruct::Reader vatId, AnyPointer::Reader objectId);
 
   template <typename>
   friend class capnp::RpcSystem;

c++/src/capnp/rpc.c++

@@ -2628,13 +2628,13 @@ public:
     });
   }
 
-  Capability::Client bootstrap(_::StructReader vatId) {
+  Capability::Client bootstrap(AnyStruct::Reader vatId) {
     // For now we delegate to restore() since it's equivalent, but eventually we'll remove restore()
     // and implement bootstrap() directly.
     return restore(vatId, AnyPointer::Reader());
   }
 
-  Capability::Client restore(_::StructReader vatId, AnyPointer::Reader objectId) {
+  Capability::Client restore(AnyStruct::Reader vatId, AnyPointer::Reader objectId) {
     KJ_IF_MAYBE(connection, network.baseConnect(vatId)) {
       auto& state = getConnectionState(kj::mv(*connection));
       return Capability::Client(state.restore(objectId));
@@ -2726,12 +2726,12 @@ RpcSystemBase::RpcSystemBase(VatNetworkBase& network, SturdyRefRestorerBase& res
 RpcSystemBase::RpcSystemBase(RpcSystemBase&& other) noexcept = default;
 RpcSystemBase::~RpcSystemBase() noexcept(false) {}
 
-Capability::Client RpcSystemBase::baseBootstrap(_::StructReader vatId) {
+Capability::Client RpcSystemBase::baseBootstrap(AnyStruct::Reader vatId) {
   return impl->bootstrap(vatId);
 }
 
 Capability::Client RpcSystemBase::baseRestore(
-    _::StructReader hostId, AnyPointer::Reader objectId) {
+    AnyStruct::Reader hostId, AnyPointer::Reader objectId) {
   return impl->restore(hostId, objectId);
 }
 

c++/src/capnp/rpc.h

@@ -353,7 +353,7 @@ public:
 
 private:
   kj::Maybe<kj::Own<_::VatNetworkBase::Connection>>
-      baseConnect(_::StructReader hostId) override final;
+      baseConnect(AnyStruct::Reader hostId) override final;
   kj::Promise<kj::Own<_::VatNetworkBase::Connection>> baseAccept() override final;
 };
 
@@ -372,8 +372,8 @@ template <typename SturdyRef, typename ProvisionId, typename RecipientId,
           typename ThirdPartyCapId, typename JoinResult>
 kj::Maybe<kj::Own<_::VatNetworkBase::Connection>>
     VatNetwork<SturdyRef, ProvisionId, RecipientId, ThirdPartyCapId, JoinResult>::
-    baseConnect(_::StructReader ref) {
-  auto maybe = connect(typename SturdyRef::Reader(ref));
+    baseConnect(AnyStruct::Reader ref) {
+  auto maybe = connect(ref.as<SturdyRef>());
   return maybe.map([](kj::Own<Connection>& conn) -> kj::Own<_::VatNetworkBase::Connection> {
     return kj::mv(conn);
   });