KT-2752: declare properties as a pair of functions when accessors are marked with @JsName

compiler/testData/diagnostics/testsWithJsStdLib/name/jsNameOnAccessors.kt

@@ -0,0 +1,7 @@
+package foo
+
+class A {
+    var x: Int
+        <!JS_NAME_CLASH!>@JsName("xx") get() = 0<!>
+        <!JS_NAME_CLASH!>@JsName("xx") set(value) {}<!>
+}

compiler/testData/diagnostics/testsWithJsStdLib/name/jsNameOnAccessors.txt

@@ -0,0 +1,12 @@
+package
+
+package foo {
+
+    public final class A {
+        public constructor A()
+        public final var x: kotlin.Int
+        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
+    }
+}