Copy: Support top-level declarations

idea/testData/refactoring/copy/copyMemberProperty/after/bar/A.kt

@@ -0,0 +1,6 @@
+package bar
+
+class A {
+    val x = 1
+    val y = x
+}

idea/testData/refactoring/copy/copyMemberProperty/after/foo/test.kt

@@ -0,0 +1,6 @@
+package foo
+
+class A {
+    val x = 1
+    val y = x
+}

idea/testData/refactoring/copy/copyMemberProperty/before/foo/test.kt

@@ -0,0 +1,6 @@
+package foo
+
+class A {
+    val <caret>x = 1
+    val y = x
+}

idea/testData/refactoring/copy/copyMemberProperty/copyMemberProperty.test

@@ -0,0 +1,4 @@
+{
+  "mainFile": "foo/test.kt",
+  "targetPackage": "bar"
+}