Xcode 9.0 (9A235) fix.

Author: kzaher

Tests/RxCocoaTests/RuntimeStateSnapshot.swift

@@ -13,7 +13,7 @@ final class ObjectRuntimeState {
     let actingAs: ClassRuntimeState
 
     init(target: AnyObject) {
-        assert(object_getClass(target) == type(of: target))
+        assert(object_getClass(target).isSubclass(of: type(of: target)))
         real = ClassRuntimeState(object_getClass(target))
         actingAs = ClassRuntimeState(RXObjCTestRuntime.objCClass(target))
     }

Tests/RxSwiftTests/DisposableTest.swift

@@ -11,6 +11,7 @@ import RxSwift
 import RxTest
 
 import class Dispatch.DispatchQueue
+import class Dispatch.DispatchSpecificKey
 #if os(Linux)
     import func Glibc.random
 #else