Refactor JS tests: unified package name, test JS specific map implementations only in JS.

Add required files to build StdLibTestToJSTest.
Remove tests StdLibMapJsTest and StdLibSetJsTest because they are tested elsewhere.

libraries/stdlib/test/collections/ComparisonDSL.kt

@@ -0,0 +1,28 @@
+package test.collections
+
+import kotlin.test.*
+
+public fun compare<T>(expected: T, actual: T, block:CompareContext<T>.() -> Unit) {
+    CompareContext(expected, actual).block()
+}
+
+public class CompareContext<out T>(public val expected: T, public val actual: T) {
+
+    public fun equals(message: String = "") {
+        assertEquals(expected, actual, message)
+    }
+    public fun propertyEquals<P>(message: String = "", getter: T.() -> P) {
+        assertEquals(expected.getter(), actual.getter(), message)
+    }
+    public fun propertyFails(getter: T.() -> Unit) { assertFailEquals({expected.getter()}, {actual.getter()}) }
+    public fun compareProperty<P>(getter: T.() -> P, block: CompareContext<P>.() -> Unit) {
+        compare(expected.getter(), actual.getter(), block)
+    }
+
+    private fun assertFailEquals(expected: () -> Unit, actual: () -> Unit) {
+        val expectedFail = fails(expected)
+        val actualFail = fails(actual)
+        //assertEquals(expectedFail != null, actualFail != null)
+        assertTypeEquals(expectedFail, actualFail)
+    }
+}