Forbid private 'expect' declarations

#KT-19170 Fixed

compiler/testData/diagnostics/tests/multiplatform/headerClass/privateMembers.kt

@@ -0,0 +1,22 @@
+// !LANGUAGE: +MultiPlatformProjects
+// MODULE: m1-common
+// FILE: common.kt
+
+expect class A {
+    <!EXPECTED_PRIVATE_DECLARATION, JVM:EXPECTED_PRIVATE_DECLARATION!>private<!> fun foo()
+    <!EXPECTED_PRIVATE_DECLARATION, JVM:EXPECTED_PRIVATE_DECLARATION!>private<!> val bar: String
+    <!EXPECTED_PRIVATE_DECLARATION, JVM:EXPECTED_PRIVATE_DECLARATION!>private<!> fun Int.memExt(): Any
+
+    <!EXPECTED_PRIVATE_DECLARATION, JVM:EXPECTED_PRIVATE_DECLARATION!>private<!> class Nested
+}
+
+// MODULE: m1-jvm(m1-common)
+// FILE: jvm.kt
+
+actual class A {
+    private fun <!ACTUAL_MISSING!>foo<!>() {}
+    private val <!ACTUAL_MISSING!>bar<!>: String = ""
+    actual private fun Int.memExt(): Any = 0
+
+    actual private class Nested
+}

compiler/testData/diagnostics/tests/multiplatform/headerClass/privateMembers.txt

@@ -0,0 +1,38 @@
+// -- Module: <m1-common> --
+package
+
+public final expect class A {
+    private expect final val bar: kotlin.String
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    private final expect fun foo(): kotlin.Unit
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+    private final expect fun kotlin.Int.memExt(): kotlin.Any
+
+    private final expect class Nested {
+        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
+    }
+}
+
+
+// -- Module: <m1-jvm> --
+package
+
+public final actual class A {
+    public constructor A()
+    private final val bar: kotlin.String = ""
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    private final fun foo(): kotlin.Unit
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+    private final actual fun kotlin.Int.memExt(): kotlin.Any
+
+    private final actual class Nested {
+        public constructor Nested()
+        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
+    }
+}

compiler/testData/diagnostics/tests/multiplatform/privateTopLevelDeclarations.kt

@@ -0,0 +1,18 @@
+// !LANGUAGE: +MultiPlatformProjects
+// MODULE: m1-common
+// FILE: common.kt
+
+<!EXPECTED_PRIVATE_DECLARATION, JVM:EXPECTED_PRIVATE_DECLARATION!>private<!> expect fun foo()
+<!EXPECTED_PRIVATE_DECLARATION, JVM:EXPECTED_PRIVATE_DECLARATION!>private<!> expect val bar: String
+<!EXPECTED_PRIVATE_DECLARATION, JVM:EXPECTED_PRIVATE_DECLARATION!>private<!> expect fun Int.memExt(): Any
+
+<!EXPECTED_PRIVATE_DECLARATION, JVM:EXPECTED_PRIVATE_DECLARATION!>private<!> expect class Foo
+
+// MODULE: m2-jvm(m1-common)
+// FILE: jvm.kt
+
+private actual fun foo() {}
+private actual val bar: String = ""
+private actual fun Int.memExt(): Any = 0
+
+private actual class Foo

compiler/testData/diagnostics/tests/multiplatform/privateTopLevelDeclarations.txt

@@ -0,0 +1,27 @@
+// -- Module: <m1-common> --
+package
+
+private expect val bar: kotlin.String
+private expect fun foo(): kotlin.Unit
+private expect fun kotlin.Int.memExt(): kotlin.Any
+
+private final expect class Foo {
+    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
+}
+
+
+// -- Module: <m2-jvm> --
+package
+
+private actual val bar: kotlin.String = ""
+private actual fun foo(): kotlin.Unit
+private actual fun kotlin.Int.memExt(): kotlin.Any
+
+private final actual class Foo {
+    public constructor Foo()
+    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
+}