Implement CODESIZE

Signed-off-by: xermicus <cyrill@parity.io>

crates/integration/src/cases.rs

@@ -126,6 +126,8 @@ sol!(
 sol!(
     contract ExtCode {
         function ExtCodeSize(address who) public view returns (uint ret);
+
+        function CodeSize() public pure returns (uint ret);
     }
 );
 
@@ -461,6 +463,18 @@ impl Contract {
         }
     }
 
+    pub fn code_size() -> Self {
+        let code = include_str!("../contracts/ExtCode.sol");
+        let name = "ExtCode";
+
+        Self {
+            name,
+            evm_runtime: crate::compile_evm_bin_runtime(name, code),
+            pvm_runtime: crate::compile_blob(name, code),
+            calldata: ExtCode::CodeSizeCall::new(()).abi_encode(),
+        }
+    }
+
     pub fn memcpy(payload: Vec<u8>) -> Self {
         let code = include_str!("../contracts/MCopy.sol");
         let name = "MCopy";