[NI] Correctly compute definitely not null type for intersection one

{ T : Any? & Foo & Bar? }!! -> { T!! & Foo & Bar }

 Also, fix bug with loosing non-representative number type.
 For example, for type { Byte & SomeType } we lost type `Byte` because
 `getDefaultPrimitiveNumberType` returns null for it

 Fixes #KT-28334 for NI

compiler/testData/diagnostics/tests/generics/nullability/inferNotNullTypeFromIntersectionOfNullableTypes.kt

@@ -0,0 +1,38 @@
+// !LANGUAGE: +NewInference
+
+fun simpleTypeAndNumberType(b: Comparable<*>?) {
+    if (b is Byte?) {
+        <!DEBUG_INFO_SMARTCAST!>b<!>!!.dec()
+    }
+}
+
+fun <T> typeParmeterAndNumberType(b: T?) {
+    if (b is Byte?) {
+        b!!.dec()
+    }
+}
+
+fun anyAndNumberType(b: Any?) {
+    if (b is Byte?) {
+        <!DEBUG_INFO_SMARTCAST!>b<!>!!.dec()
+    }
+}
+
+fun comparableAndNumberType(b: Comparable<Byte>?) {
+    if (b is Byte?) {
+        <!DEBUG_INFO_SMARTCAST!>b<!>!!.dec()
+    }
+}
+
+object SeparateTypes {
+    interface A
+    interface B {
+        fun foo() {}
+    }
+
+    fun separate(a: A?) {
+        if (a is B?) {
+            a!!.foo()
+        }
+    }
+}

compiler/testData/diagnostics/tests/generics/nullability/inferNotNullTypeFromIntersectionOfNullableTypes.txt

@@ -0,0 +1,27 @@
+package
+
+public fun anyAndNumberType(/*0*/ b: kotlin.Any?): kotlin.Unit
+public fun comparableAndNumberType(/*0*/ b: kotlin.Comparable<kotlin.Byte>?): kotlin.Unit
+public fun simpleTypeAndNumberType(/*0*/ b: kotlin.Comparable<*>?): kotlin.Unit
+public fun </*0*/ T> typeParmeterAndNumberType(/*0*/ b: T?): kotlin.Unit
+
+public object SeparateTypes {
+    private constructor SeparateTypes()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public final fun separate(/*0*/ a: SeparateTypes.A?): kotlin.Unit
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+
+    public interface A {
+        public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+        public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+        public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+    }
+
+    public interface B {
+        public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+        public open fun foo(): kotlin.Unit
+        public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+        public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+    }
+}