Type Checker: Fix internal error when applying unary operators to tuples with empty components

test/libsolidity/syntaxTests/iceRegressionTests/declarationUnaryTuple/declaration_bitnot_tuple.sol

@@ -0,0 +1,9 @@
+contract C
+{
+    function f() public
+    {
+        int x = ~(0,);
+    }
+}
+// ----
+// TypeError: (60-64): Tuple component cannot be empty.

test/libsolidity/syntaxTests/iceRegressionTests/declarationUnaryTuple/declaration_dec_tuple.sol

@@ -0,0 +1,9 @@
+contract C
+{
+    function f() public
+    {
+        int x = --(,);
+    }
+}
+// ----
+// TypeError: (59-64): Unary operator -- cannot be applied to type tuple(,)

test/libsolidity/syntaxTests/iceRegressionTests/declarationUnaryTuple/declaration_delete_tuple.sol

@@ -0,0 +1,10 @@
+contract C
+{
+    function f() public
+    {
+        int x = delete (,0);
+    }
+}
+// ----
+// TypeError: (68-69): Expression has to be an lvalue.
+// TypeError: (59-70): Unary operator delete cannot be applied to type tuple(,int_const 0)

test/libsolidity/syntaxTests/iceRegressionTests/declarationUnaryTuple/declaration_inc_tuple.sol

@@ -0,0 +1,9 @@
+contract C
+{
+    function f() public
+    {
+        (int x) = ++(,);
+    }
+}
+// ----
+// TypeError: (61-66): Unary operator ++ cannot be applied to type tuple(,)

test/libsolidity/syntaxTests/iceRegressionTests/declarationUnaryTuple/declaration_unary_tuple.sol

@@ -0,0 +1,20 @@
+contract C
+{
+    function f() public
+    {
+        int x = +(0, 0);
+        int y = -(0, 0);
+        (int z) = ~(0, 0);
+        (int t) = !(0, 0);
+    }
+}
+// ----
+// SyntaxError: (59-66): Use of unary + is disallowed.
+// TypeError: (59-66): Unary operator + cannot be applied to type tuple(int_const 0,int_const 0)
+// TypeError: (51-66): Different number of components on the left hand side (1) than on the right hand side (2).
+// TypeError: (84-91): Unary operator - cannot be applied to type tuple(int_const 0,int_const 0)
+// TypeError: (76-91): Different number of components on the left hand side (1) than on the right hand side (2).
+// TypeError: (111-118): Unary operator ~ cannot be applied to type tuple(int_const 0,int_const 0)
+// TypeError: (101-118): Different number of components on the left hand side (1) than on the right hand side (2).
+// TypeError: (138-145): Unary operator ! cannot be applied to type tuple(int_const 0,int_const 0)
+// TypeError: (128-145): Different number of components on the left hand side (1) than on the right hand side (2).