Get rid of CompileKotlinAgainstMultifileKotlinTestGenerated and boxMultifileClasses/

Merge tests in boxMultifileClasses/calls to one test case; copy the two
resulting tests (+ change box to main) to compileKotlinAgainstKotlin

compiler/testData/codegen/boxMultiFile/callsToMultifileClassFromOtherPackage.kt

@@ -0,0 +1,23 @@
+// FILE: 1.kt
+
+import a.*
+
+fun box(): String {
+    if (foo() != "OK") return "Fail function"
+    if (constOK != "OK") return "Fail const"
+    if (valOK != "OK") return "Fail val"
+    varOK = "OK"
+    if (varOK != "OK") return "Fail var"
+
+    return "OK"
+}
+
+// FILE: 2.kt
+
+@file:[JvmName("MultifileClass") JvmMultifileClass]
+package a
+
+fun foo(): String = "OK"
+const val constOK: String = "OK"
+val valOK: String = "OK"
+var varOK: String = "Hmmm?"

compiler/testData/codegen/boxMultiFile/constPropertyReferenceFromMultifileClass.kt

@@ -0,0 +1,26 @@
+// FILE: 1.kt
+
+import a.OK
+
+fun box(): String {
+    val okRef = ::OK
+
+    // TODO: see KT-10892
+//    val annotations = okRef.annotations
+//    val numAnnotations = annotations.size
+//    if (numAnnotations != 1) {
+//        return "Failed, annotations: $annotations"
+//    }
+
+    return okRef.get()
+}
+
+// FILE: 2.kt
+
+@file:[JvmName("MultifileClass") JvmMultifileClass]
+package a
+
+annotation class A
+
+@A
+const val OK: String = "OK"