[SMTChecker] Fix ICE when tuples have extra effectless parens

test/libsolidity/smtCheckerTests/types/tuple_extra_parens_1.sol

@@ -0,0 +1,7 @@
+pragma experimental SMTChecker;
+contract C {
+	function f2() public pure returns(int) {
+		int a;
+		((, a)) = (1, 2);
+	}
+}

test/libsolidity/smtCheckerTests/types/tuple_extra_parens_2.sol

@@ -0,0 +1,7 @@
+pragma experimental SMTChecker;
+contract C {
+	function f2() public pure returns(int) {
+		int a;
+		(((, a),)) = ((1, 2), 3);
+	}
+}

test/libsolidity/smtCheckerTests/types/tuple_extra_parens_3.sol

@@ -0,0 +1,7 @@
+pragma experimental SMTChecker;
+contract C {
+	function f2() public pure returns(int) {
+		int a;
+		(((((((, a),)))))) = ((1, 2), 3);
+	}
+}

test/libsolidity/smtCheckerTests/types/tuple_extra_parens_4.sol

@@ -0,0 +1,7 @@
+pragma experimental SMTChecker;
+contract C {
+	function f2() public pure returns(int) {
+		int a;
+		((((((, a)))),)) = ((1, 2), 3);
+	}
+}

test/libsolidity/smtCheckerTests/types/tuple_extra_parens_5.sol

@@ -0,0 +1,7 @@
+pragma experimental SMTChecker;
+contract C {
+	function f2() public pure returns(int) {
+		int a;
+		((((((((((((, a))))))),))))) = ((1, 2), 3);
+	}
+}

test/libsolidity/smtCheckerTests/types/tuple_extra_parens_6.sol

@@ -0,0 +1,6 @@
+pragma experimental SMTChecker;
+contract C {
+	function f() public pure {
+		(((,))) = ((2),3);
+	}
+}