KT-5214 Annotation to provide platform name to avoid signature conflict

#KT-5214 Fixed

compiler/testData/codegen/boxWithStdlib/platformNames/callableReference.kt

@@ -0,0 +1,11 @@
+import kotlin.platform.*
+
+[platformName("bar")]
+fun foo() = "foo"
+
+fun box(): String {
+    val f = (::foo)()
+    if (f != "foo") return "Fail: $f"
+
+    return "OK"
+}

compiler/testData/codegen/boxWithStdlib/platformNames/clashingErasure.kt

@@ -0,0 +1,16 @@
+import kotlin.platform.*
+
+fun <T> List<T>.foo() = "foo"
+
+[platformName("fooInt")]
+fun List<Int>.foo() = "fooInt"
+
+fun box(): String {
+    val strings = listOf("", "").foo()
+    if (strings != "foo") return "Fail: $strings"
+
+    val ints = listOf(1, 2).foo()
+    if (ints != "fooInt") return "Fail: $ints"
+
+    return "OK"
+}

compiler/testData/codegen/boxWithStdlib/platformNames/functionName.kt

@@ -0,0 +1,11 @@
+import kotlin.platform.*
+
+[platformName("bar")]
+fun foo() = "foo"
+
+fun box(): String {
+    val f = foo()
+    if (f != "foo") return "Fail: $f"
+
+    return "OK"
+}

compiler/testData/codegen/boxWithStdlib/platformNames/propertyName.kt

@@ -0,0 +1,14 @@
+import kotlin.platform.*
+
+var v: Int = 1
+    [platformName("vget")]
+    get
+    [platformName("vset")]
+    set
+
+fun box(): String {
+    v += 1
+    if (v != 2) return "Fail: $v"
+
+    return "OK"
+}