parser: correct error position on field and method errors

vlib/v/checker/tests/inout/unknown_field.out

@@ -0,0 +1,6 @@
+vlib/v/checker/tests/inout/unknown_field.v:7:12: error: unknown field `checker.Test.sdd`
+    5| fn main() {
+    6|     t := Test{}
+    7|     println(t.sdd)
+                     ~~~
+    8| }

vlib/v/checker/tests/inout/unknown_field.vv

@@ -0,0 +1,8 @@
+module checker
+
+struct Test {}
+
+fn main() {
+	t := Test{}
+	println(t.sdd)
+}

vlib/v/checker/tests/inout/unknown_method.out

@@ -0,0 +1,6 @@
+vlib/v/checker/tests/inout/unknown_method.v:7:12: error: unknown method: checker.Test.sdd
+    5| fn main() {
+    6|     t := Test{}
+    7|     println(t.sdd())
+                     ~~~~~
+    8| }

vlib/v/checker/tests/inout/unknown_method.vv

@@ -0,0 +1,8 @@
+module checker
+
+struct Test {}
+
+fn main() {
+	t := Test{}
+	println(t.sdd())
+}

vlib/v/parser/parser.v

@@ -953,17 +953,18 @@ fn (p mut Parser) filter() {
 
 fn (p mut Parser) dot_expr(left ast.Expr) ast.Expr {
 	p.next()
+	mut name_pos := p.tok.position()
 	field_name := p.check_name()
 	is_filter := field_name in ['filter', 'map']
 	if is_filter {
 		p.open_scope()
+		name_pos = p.tok.position()
 		p.filter()
 		// wrong tok position when using defer
 		// defer {
 		// p.close_scope()
 		// }
 	}
-	pos := p.tok.position()
 	// Method call
 	if p.tok.kind == .lpar {
 		p.next()
@@ -986,6 +987,12 @@ fn (p mut Parser) dot_expr(left ast.Expr) ast.Expr {
 			or_stmts = p.parse_block_no_scope()
 			p.close_scope()
 		}
+		end_pos := p.tok.position()
+		pos := token.Position{
+			line_nr: name_pos.line_nr
+			pos: name_pos.pos
+			len: end_pos.pos - name_pos.pos
+		}
 		mcall_expr := ast.CallExpr{
 			left: left
 			name: field_name
@@ -1007,7 +1014,7 @@ fn (p mut Parser) dot_expr(left ast.Expr) ast.Expr {
 	sel_expr := ast.SelectorExpr{
 		expr: left
 		field: field_name
-		pos: p.tok.position()
+		pos: name_pos
 	}
 	mut node := ast.Expr{}
 	node = sel_expr