Add more tests to ViewPureChecker

test/libsolidity/syntaxTests/viewPureChecker/view_pure_abi_encode_arguments.sol

@@ -0,0 +1,36 @@
+contract C {
+    uint x;
+    function gView() public view returns (uint) { return x; }
+    function gNonPayable() public returns (uint) { x = 4; return 0; }
+
+    function f1() view public returns (bytes memory) {
+        return abi.encode(gView());
+    }
+    function f2() view public returns (bytes memory) {
+        return abi.encodePacked(gView());
+    }
+    function f3() view public returns (bytes memory) {
+        return abi.encodeWithSelector(0x12345678, gView());
+    }
+    function f4() view public returns (bytes memory) {
+        return abi.encodeWithSignature("f(uint256)", gView());
+    }
+    function g1() public returns (bytes memory) {
+        return abi.encode(gNonPayable());
+    }
+    function g2() public returns (bytes memory) {
+        return abi.encodePacked(gNonPayable());
+    }
+    function g3() public returns (bytes memory) {
+        return abi.encodeWithSelector(0x12345678, gNonPayable());
+    }
+    function g4() public returns (bytes memory) {
+        return abi.encodeWithSignature("f(uint256)", gNonPayable());
+    }
+    // This will generate the only warning.
+    function check() public returns (bytes memory) {
+        return abi.encode(2);
+    }
+}
+// ----
+// Warning 2018: (1100-1184): Function state mutability can be restricted to pure