Contracts: use compiled rust tests (#2347)

see #2189

This PR does the following:
- Bring the user api functions into a new pallet-contracts-uapi (They
are currently defined in ink!
[here])(https://github.com/paritytech/ink/blob/master/crates/env/src/engine/on_chain/ext.rs)
- Add older api versions and unstable to the user api trait.
- Remove pallet-contracts-primitives and bring the types it defined in
uapi / pallet-contracts
- Add the infrastructure to build fixtures from Rust files and test it
works by replacing `dummy.wat` and `call.wat`
- Move all the doc from wasm/runtime.rs to pallet-contracts-uapi.

This will be done in a follow up:
- convert the rest of the test from .wat to rust
- bring risc-v uapi up to date with wasm
- finalize the uapi host fns, making sure everything is codegen from the
source host fns in pallet-contracts

---------

Co-authored-by: Alexander Theißen <alex.theissen@me.com>

substrate/frame/contracts/src/wasm/mod.rs

@@ -24,13 +24,13 @@ mod runtime;
 #[cfg(doc)]
 pub use crate::wasm::runtime::api_doc;
 
-#[cfg(test)]
-pub use tests::MockExt;
-
 pub use crate::wasm::runtime::{
-	AllowDeprecatedInterface, AllowUnstableInterface, CallFlags, Environment, ReturnCode, Runtime,
+	AllowDeprecatedInterface, AllowUnstableInterface, Environment, ReturnErrorCode, Runtime,
 	RuntimeCosts,
 };
+pub use pallet_contracts_uapi::ReturnFlags;
+#[cfg(test)]
+pub use tests::MockExt;
 
 use crate::{
 	exec::{ExecResult, Executable, ExportedFunction, Ext},
@@ -436,6 +436,7 @@ mod tests {
 	use crate::{
 		exec::{AccountIdOf, ErrorOrigin, ExecError, Executable, Ext, Key, SeedOf},
 		gas::GasMeter,
+		primitives::ExecReturnValue,
 		storage::WriteOutcome,
 		tests::{RuntimeCall, Test, ALICE, BOB},
 		BalanceOf, CodeHash, Error, Origin, Pallet as Contracts,
@@ -445,7 +446,7 @@ mod tests {
 		assert_err, assert_ok, dispatch::DispatchResultWithPostInfo, weights::Weight,
 	};
 	use frame_system::pallet_prelude::BlockNumberFor;
-	use pallet_contracts_primitives::{ExecReturnValue, ReturnFlags};
+	use pallet_contracts_uapi::ReturnFlags;
 	use pretty_assertions::assert_eq;
 	use sp_core::H256;
 	use sp_runtime::DispatchError;
@@ -2739,7 +2740,7 @@ mod tests {
 		let result = execute(CODE, input, &mut ext).unwrap();
 		assert_eq!(
 			u32::from_le_bytes(result.data[0..4].try_into().unwrap()),
-			ReturnCode::KeyNotFound as u32
+			ReturnErrorCode::KeyNotFound as u32
 		);
 
 		// value exists
@@ -2747,7 +2748,7 @@ mod tests {
 		let result = execute(CODE, input, &mut ext).unwrap();
 		assert_eq!(
 			u32::from_le_bytes(result.data[0..4].try_into().unwrap()),
-			ReturnCode::Success as u32
+			ReturnErrorCode::Success as u32
 		);
 		assert_eq!(ext.storage.get(&[1u8; 64].to_vec()).unwrap(), &[42u8]);
 		assert_eq!(&result.data[4..], &[42u8]);
@@ -2757,7 +2758,7 @@ mod tests {
 		let result = execute(CODE, input, &mut ext).unwrap();
 		assert_eq!(
 			u32::from_le_bytes(result.data[0..4].try_into().unwrap()),
-			ReturnCode::Success as u32
+			ReturnErrorCode::Success as u32
 		);
 		assert_eq!(ext.storage.get(&[2u8; 19].to_vec()), Some(&vec![]));
 		assert_eq!(&result.data[4..], &([] as [u8; 0]));
@@ -2920,7 +2921,7 @@ mod tests {
 		let result = execute(CODE, input, &mut ext).unwrap();
 		assert_eq!(
 			u32::from_le_bytes(result.data[0..4].try_into().unwrap()),
-			ReturnCode::KeyNotFound as u32
+			ReturnErrorCode::KeyNotFound as u32
 		);
 
 		// value did exist -> value returned
@@ -2928,7 +2929,7 @@ mod tests {
 		let result = execute(CODE, input, &mut ext).unwrap();
 		assert_eq!(
 			u32::from_le_bytes(result.data[0..4].try_into().unwrap()),
-			ReturnCode::Success as u32
+			ReturnErrorCode::Success as u32
 		);
 		assert_eq!(ext.storage.get(&[1u8; 64].to_vec()), None);
 		assert_eq!(&result.data[4..], &[42u8]);
@@ -2938,7 +2939,7 @@ mod tests {
 		let result = execute(CODE, input, &mut ext).unwrap();
 		assert_eq!(
 			u32::from_le_bytes(result.data[0..4].try_into().unwrap()),
-			ReturnCode::Success as u32
+			ReturnErrorCode::Success as u32
 		);
 		assert_eq!(ext.storage.get(&[2u8; 19].to_vec()), None);
 		assert_eq!(&result.data[4..], &[0u8; 0]);