In java/java.go, enhance the checking logic for Dependency interface implementation

Add nil checking for Dependency interface implementation

Bug: 121985695

Test: 1. m aidegen
      2. $ANDROID_HOST_OUT/bin/aidegen framework
      3. check import static android.Manifest.permission.BIND_VOICE_INTERACTION;
	 denpendency should be resolved in frameworks/base/services/core/java/com/android/server/am/ActivityManagerService.java

Change-Id: Ibac280ce3de2537f453c4ca7e8f79f55667f1fa0