InvertIfConditionAction: preserve comments after last statement

Fixes IDEA-153371 invert 'if' condition deletes comment lines

java/java-tests/testData/codeInsight/invertIfCondition/beforeConditionWithComment.java

@@ -0,0 +1,12 @@
+// "Invert 'if' condition" "true"
+class A {
+    // IDEA-153371
+    public void foo() {
+        String value ="not-null";
+
+        <caret>if (value != null) {
+            System.out.println(value);
+            // Comment gets deleted.
+        }
+    }
+}