Added tests for function type that would be packed in storage

test/libsolidity/semanticTests/functionTypes/packed_in_storage.sol

@@ -0,0 +1,25 @@
+contract C {
+    uint8 public a = 20;
+    function() external public f = this.g;
+    function g() external {
+    }
+    function slots() public returns (uint _a, uint _f) {
+        assembly {
+            _a := a.slot
+            _f := f.slot
+        }
+    }
+    function offsets() public returns (uint _a, uint _f) {
+        assembly {
+            _a := a.offset
+            _f := f.offset
+        }
+    }
+}
+// ====
+// compileViaYul: also
+// ----
+// a() -> 0x14
+// f() -> 7175878113405833249322534082293024008058894263831758935649259662147697246208
+// slots() -> 0, 0
+// offsets() -> 0, 1

test/libsolidity/semanticTests/functionTypes/packed_in_storage_internal.sol

@@ -0,0 +1,40 @@
+contract C {
+    function() internal f = g;
+    uint8 public a = 20;
+
+    function g() internal {
+    }
+    function slots() public returns (uint _a, uint _f) {
+        assembly {
+            _a := a.slot
+            _f := f.slot
+        }
+    }
+    function offsets() public returns (uint _a, uint _f) {
+        assembly {
+            _a := a.offset
+            _f := f.offset
+        }
+    }
+    function delete_a() external {
+        delete a;
+    }
+    // The actual value cannot be returned since it would be different for various settings
+    // (optimized v/s non-optimized, legacy v/s IR).
+    function test_f_non_zero() external returns (bool) {
+        uint storage_value;
+        assembly {
+            storage_value := sload(f.slot)
+        }
+        assert(storage_value != 0);
+        return true;
+    }
+}
+// ====
+// compileViaYul: also
+// ----
+// a() -> 0x14
+// slots() -> 0, 0
+// offsets() -> 8, 0
+// delete_a() ->
+// test_f_non_zero() -> true