DO NOT MERGE Fix finalization

Bug: 5321358
 Destroy does run with this. Ideally we should get rid of the need
 to run this on the UI thread at all. GL destroy should instead
 take place when the view is detached or something like that.

 Cherry picked from master

Change-Id: I693ce83cd607186173d8cf58485c5df28004e52c

core/java/android/webkit/WebView.java

@@ -4023,7 +4023,7 @@ public class WebView extends AbsoluteLayout
     protected void finalize() throws Throwable {
         try {
             if (mNativeClass != 0) {
-                post(new Runnable() {
+                mPrivateHandler.post(new Runnable() {
                     @Override
                     public void run() {
                         destroy();