Update to newer Android Lint and suppress new Lint errors

android_webview/tools/system_webview_shell/apk/src/org/chromium/webview_shell/WebViewCreateDestroyActivity.java

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package org.chromium.webview_shell;
 
+import android.annotation.SuppressLint;
 import android.app.Activity;
 import android.content.Intent;
 import android.os.Bundle;
 import android.view.ViewGroup;
 import android.webkit.WebSettings;
 import android.webkit.WebView;
 import android.webkit.WebViewClient;
 import android.widget.RelativeLayout;
 
 /**
  * This activity always has at most one live webview. Any previously exisisting
  * webview instance is destroyed first before creating a new one. This activity
  * is designed for testing create/destroy webview sequence, for catching potential
  * memory leaks and memory benchmarking.
  *
  * Note that this activity does not destroy any webviews in other activities. For
  * example launching TelemetryActivity followed by WebViewCreateDestroyActivity
  * will yield two webview instances in total.
  */
 public class WebViewCreateDestroyActivity extends Activity {
+    @SuppressLint("StaticFieldLeak")
     private static WebView sWebView;
 
     @Override
     protected void onDestroy() {
         destroyWebViewIfExists();
         super.onDestroy();
     }
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
@@ skipping 40 matching lines @@
         RelativeLayout layout = (RelativeLayout) findViewById(R.id.emptyview);
         layout.removeView(sWebView);
         sWebView.destroy();
         sWebView = null;
     }
 
     private static String getUrlFromIntent(Intent intent) {
         return intent != null ? intent.getDataString() : null;
     }
 }