FIX: synchronized statements where the lock expression is a reference to a...

FIX: synchronized statements where the lock expression is a reference to a non-final field. Such statements are unlikely to have useful semantics, as different threads may be locking on different objects even when operating on the same object.

Android/doraemonkit/src/main/java/com/didichuxing/doraemonkit/kit/blockmonitor/core/StackSampler.java

@@ -26,7 +26,7 @@ public class StackSampler {
     private HandlerThread mStackThread;
     private Handler mStackHandler;
 
-    private LinkedHashMap<Long, String> sStackMap = new LinkedHashMap<>();
+    private final LinkedHashMap<Long, String> sStackMap = new LinkedHashMap<>();
     private String mFilterCache;
 
     public void init() {