fixed bug: 'isStatement' for function body == 'hasBlockBody'

not vice versa

compiler/testData/diagnostics/tests/controlStructures/ForbidStatementAsDirectFunctionBody.kt

@@ -0,0 +1,11 @@
+
+fun foo1() = <!EXPRESSION_EXPECTED!>while (b()) {}<!>
+
+fun foo2() = <!EXPRESSION_EXPECTED!>for (<!UNUSED_PARAMETER!>i<!> in <!ITERATOR_MISSING!>10<!>) {}<!>
+
+fun foo3() = when (b()) {
+    true -> 1
+    else -> 0
+}
+
+fun b(): Boolean = true

compiler/testData/diagnostics/tests/controlStructures/kt770.kt351.kt735_StatementType.kt

@@ -42,8 +42,8 @@ fun box() : Int {
 
 //More tests
 
-fun test1() = while(true) {}
-fun test2(): Unit = while(true) {}
+fun test1() { while(true) {} }
+fun test2(): Unit { while(true) {} }
 
 fun testCoercionToUnit() {
     val <!UNUSED_VARIABLE!>simple<!>: ()-> Unit = {