Update to newer Android Lint and suppress new Lint errors

chrome/android/java/src/org/chromium/chrome/browser/ChromeActivitySessionTracker.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.chrome.browser;
 
+import android.annotation.SuppressLint;
 import android.app.Activity;
 import android.app.Application;
 import android.content.SharedPreferences;
 import android.provider.Settings;
 import android.support.annotation.Nullable;
 import android.text.TextUtils;
 
 import org.chromium.base.ApplicationState;
 import org.chromium.base.ApplicationStatus;
 import org.chromium.base.ApplicationStatus.ApplicationStateListener;
@@ skipping 19 matching lines @@
 
 import java.lang.ref.WeakReference;
 
 /**
  * Tracks the foreground session state for the Chrome activities.
  */
 public class ChromeActivitySessionTracker {
 
     private static final String PREF_LOCALE = "locale";
 
+    @SuppressLint("StaticFieldLeak")
     private static ChromeActivitySessionTracker sInstance;
 
     private final PowerBroadcastReceiver mPowerBroadcastReceiver = new PowerBroadcastReceiver();
 
     // Used to trigger variation changes (such as seed fetches) upon application foregrounding.
     private VariationsSession mVariationsSession;
 
     private Application mApplication;
     private boolean mIsInitialized;
     private boolean mIsStarted;
@@ skipping 198 matching lines @@
     }
 
     /**
      * @return The PowerBroadcastReceiver for the browser process.
      */
     @VisibleForTesting
     public PowerBroadcastReceiver getPowerBroadcastReceiverForTesting() {
         return mPowerBroadcastReceiver;
     }
 }