compiler: support all kinds of deferred builtins

This change extends defer support to all supported builitin functions.
Not all of them make sense (such as len, cap, real, imag, etc) but this
change for example adds support for `defer(delete(m, key))` which is
used in the Go 1.15 encoding/json package.

testdata/calls.go

@@ -72,7 +72,8 @@ func main() {
 	regression1033()
 
 	//Test deferred builtins
-	testDeferBuiltin()
+	testDeferBuiltinClose()
+	testDeferBuiltinDelete()
 }
 
 func runFunc(f func(int), arg int) {
@@ -121,13 +122,30 @@ func testMultiFuncVar() {
 	defer f(1)
 }
 
-func testDeferBuiltin() {
+func testDeferBuiltinClose() {
 	i := make(chan int)
-	defer close(i)
+	func() {
+		defer close(i)
+	}()
+	if n, ok := <-i; n != 0 || ok {
+		println("expected to read 0 from closed channel")
+	}
+}
+
+func testDeferBuiltinDelete() {
+	m := map[int]int{3: 30, 5: 50}
+	func() {
+		defer delete(m, 3)
+		if m[3] != 30 {
+			println("expected m[3] to be 30")
+		}
+	}()
+	if m[3] != 0 {
+		println("expected m[3] to be 0")
+	}
 }
 
 type dumb struct {
-
 }
 
 func (*dumb) Value(key interface{}) interface{} {
@@ -144,17 +162,17 @@ func exportedDefer() {
 }
 
 func deferFunc() (int, func(int)) {
-	return 0, func(i int){println("...extracted defer func ", i)}
+	return 0, func(i int) { println("...extracted defer func ", i) }
 }
 
 func multiFuncDefer() func(int) {
 	i := 0
 
 	if i > 0 {
-		return func(i int){println("Should not have gotten here. i = ", i)}
+		return func(i int) { println("Should not have gotten here. i = ", i) }
 	}
 
-	return func(i int){println("Called the correct function. i = ", i)}
+	return func(i int) { println("Called the correct function. i = ", i) }
 }
 
 func testBound(f func() string) {