Made vararg parameters have Array<out T> type

instead of simply Array<T>
  #KT-1638 Fixed
  #KT-2163 Fixed
  #KT-3213 Fixed
  #KT-4172 Fixed
  #KT-5534 Fixed

compiler/testData/diagnostics/tests/varargs/kt2163.kt

@@ -0,0 +1,7 @@
+// !DIAGNOSTICS: -UNUSED_PARAMETER
+
+fun printAll(vararg a : Any) {}
+
+fun main(args: Array<String>) {
+    printAll(*args) // Shouldn't be an error
+}

compiler/testData/diagnostics/tests/varargs/kt2163.txt

@@ -0,0 +1,4 @@
+package
+
+internal fun main(/*0*/ args: kotlin.Array<kotlin.String>): kotlin.Unit
+internal fun printAll(/*0*/ vararg a: kotlin.Any /*kotlin.Array<out kotlin.Any>*/): kotlin.Unit

compiler/testData/diagnostics/tests/varargs/varargsAndOut1.kt

@@ -0,0 +1,13 @@
+// !CHECK_TYPE
+
+fun test(vararg a: String) {
+    a checkType { it : _<Array<out String>> }
+
+    foo(a) checkType { it : _<Array<out String>> }
+}
+
+fun <T> test1(vararg t: T) {
+    t checkType { it : _<Array<out T>> }
+}
+
+fun <T> foo(a: Array<T>): Array<T> = a

compiler/testData/diagnostics/tests/varargs/varargsAndOut1.txt

@@ -0,0 +1,5 @@
+package
+
+internal fun </*0*/ T> foo(/*0*/ a: kotlin.Array<T>): kotlin.Array<T>
+internal fun test(/*0*/ vararg a: kotlin.String /*kotlin.Array<out kotlin.String>*/): kotlin.Unit
+internal fun </*0*/ T> test1(/*0*/ vararg t: T /*kotlin.Array<out T>*/): kotlin.Unit

compiler/testData/diagnostics/tests/varargs/varargsAndOut2.kt

@@ -0,0 +1,9 @@
+// !DIAGNOSTICS: -UNUSED_PARAMETER
+
+fun bar(vararg a: String) {}
+
+fun test2(a: Array<String>, b: Array<out String>) {
+    bar(*a)
+    bar(*b)
+    bar("", *a, *b, "")
+}

compiler/testData/diagnostics/tests/varargs/varargsAndOut2.txt

@@ -0,0 +1,4 @@
+package
+
+internal fun bar(/*0*/ vararg a: kotlin.String /*kotlin.Array<out kotlin.String>*/): kotlin.Unit
+internal fun test2(/*0*/ a: kotlin.Array<kotlin.String>, /*1*/ b: kotlin.Array<out kotlin.String>): kotlin.Unit

compiler/testData/diagnostics/tests/varargs/varargsAndPair.kt

@@ -0,0 +1,8 @@
+fun foo<T: Any>(vararg <!UNUSED_PARAMETER!>ts<!>: T): T? = null
+
+class Pair<A>(a: A)
+
+fun test() {
+    val v = foo(Pair(1))
+    <!TYPE_MISMATCH!>v<!>: Int // check that it is not error type
+}

compiler/testData/diagnostics/tests/varargs/varargsAndPair.txt

@@ -0,0 +1,11 @@
+package
+
+internal fun </*0*/ T : kotlin.Any> foo(/*0*/ vararg ts: T /*kotlin.Array<T>*/): T?
+internal fun test(): kotlin.Unit
+
+internal final class Pair</*0*/ A> {
+    public constructor Pair</*0*/ A>(/*0*/ a: 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
+}