Fixed KT-5434 J2K: incorrect conversion of main method

#KT-5434 Fixed

j2k/tests/testData/ast/function/main2.java

@@ -0,0 +1,5 @@
+//file
+public class A {
+    public static void main(String[] args) {
+    }
+}

j2k/tests/testData/ast/function/main2.kt

@@ -0,0 +1,7 @@
+public class A {
+    class object {
+        public fun main(args: Array<String>) {
+        }
+    }
+}
+fun main(args: Array<String>) = A.main(args)

j2k/tests/testData/ast/function/mainAndNullabilitySetting.java

@@ -0,0 +1,6 @@
+// !forceNotNullTypes: false
+//file
+public class A {
+    public static void main(String[] args) {
+    }
+}

j2k/tests/testData/ast/function/mainAndNullabilitySetting.kt

@@ -0,0 +1,8 @@
+// !forceNotNullTypes: false
+public class A {
+    class object {
+        public fun main(args: Array<String>) {
+        }
+    }
+}
+fun main(args: Array<String>) = A.main(args)

j2k/tests/testData/ast/issues/kt-638.kt

@@ -31,4 +31,4 @@ public class User {
         }
     }
 }
-fun main(args: Array<String>) = User.main(args as Array<String?>?)
+fun main(args: Array<String>) = User.main(args)

j2k/tests/testData/ast/issues/kt-871.kt

@@ -7,4 +7,4 @@ class Program {
         }
     }
 }
-fun main(args: Array<String>) = Program.main(args as Array<String?>?)
+fun main(args: Array<String>) = Program.main(args)

j2k/tests/testData/ast/switch/comlicatedFallDown.kt

@@ -83,4 +83,4 @@ public class SwitchDemo {
         }
     }
 }
-fun main(args: Array<String>) = SwitchDemo.main(args as Array<String?>?)
+fun main(args: Array<String>) = SwitchDemo.main(args)

j2k/tests/testData/ast/switch/emptySwitch.kt

@@ -11,4 +11,4 @@ public class NonDefault {
         }
     }
 }
-fun main(args: Array<String>) = NonDefault.main(args as Array<String?>?)
+fun main(args: Array<String>) = NonDefault.main(args)

j2k/tests/testData/ast/switch/fallDown.kt

@@ -13,4 +13,4 @@ public class SwitchDemo {
         }
     }
 }
-fun main(args: Array<String>) = SwitchDemo.main(args as Array<String?>?)
+fun main(args: Array<String>) = SwitchDemo.main(args)

j2k/tests/testData/ast/switch/kt-539.kt

@@ -25,4 +25,4 @@ public class SwitchDemo {
         }
     }
 }
-fun main(args: Array<String>) = SwitchDemo.main(args as Array<String?>?)
+fun main(args: Array<String>) = SwitchDemo.main(args)

j2k/tests/testData/ast/switch/nondefault.kt

@@ -13,4 +13,4 @@ public class NonDefault {
         }
     }
 }
-fun main(args: Array<String>) = NonDefault.main(args as Array<String?>?)
+fun main(args: Array<String>) = NonDefault.main(args)