android: Remove redundant code to suspend timers in the background

chrome/android/java/src/org/chromium/chrome/browser/ChromeApplication.java

 // Copyright 2013 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.app.Activity;
 import android.content.Context;
 import android.content.Intent;
 import android.content.SharedPreferences;
@@ skipping 82 matching lines @@
 import org.chromium.chrome.browser.tabmodel.document.DocumentTabModelSelector;
 import org.chromium.chrome.browser.tabmodel.document.StorageDelegate;
 import org.chromium.chrome.browser.tabmodel.document.TabDelegate;
 import org.chromium.chrome.browser.util.FeatureUtilities;
 import org.chromium.components.sync.signin.AccountManagerDelegate;
 import org.chromium.components.sync.signin.AccountManagerHelper;
 import org.chromium.components.sync.signin.SystemAccountManagerDelegate;
 import org.chromium.content.app.ContentApplication;
 import org.chromium.content.browser.ChildProcessCreationParams;
 import org.chromium.content.browser.ChildProcessLauncher;
-import org.chromium.content.browser.ContentViewStatics;
 import org.chromium.content.common.ContentSwitches;
 import org.chromium.policy.AppRestrictionsProvider;
 import org.chromium.policy.CombinedPolicyProvider;
 import org.chromium.policy.CombinedPolicyProvider.PolicyChangeListener;
 import org.chromium.printing.PrintingController;
 import org.chromium.ui.UiUtils;
 import org.chromium.ui.base.ActivityWindowAndroid;
 import org.chromium.ui.base.ResourceBundle;
 
 import java.lang.ref.WeakReference;
@@ skipping 10 matching lines @@
     private static final String PREF_BOOT_TIMESTAMP =
             "com.google.android.apps.chrome.ChromeMobileApplication.BOOT_TIMESTAMP";
     private static final long BOOT_TIMESTAMP_MARGIN_MS = 1000;
     private static final String PREF_LOCALE = "locale";
     private static final String DEV_TOOLS_SERVER_SOCKET_PREFIX = "chrome";
     private static final String SESSIONS_UUID_PREF_KEY = "chromium.sync.sessions.id";
 
     private static boolean sIsFinishedCachingNativeFlags;
     private static DocumentTabModelSelector sDocumentTabModelSelector;
 
-    /**
-     * This class allows pausing scripts & network connections when we
-     * go to the background and resume when we are back in foreground again.
-     * TODO(pliard): Get rid of this class once JavaScript timers toggling is done directly on
-     * the native side by subscribing to the system monitor events.
-     */
-    private static class BackgroundProcessing {
-        private class SuspendRunnable implements Runnable {
-            @Override
-            public void run() {
-                mSuspendRunnable = null;
-                assert !mWebKitTimersAreSuspended;
-                mWebKitTimersAreSuspended = true;
-                ContentViewStatics.setWebKitSharedTimersSuspended(true);
-            }
-        }
-
-        private static final int SUSPEND_TIMERS_AFTER_MS = 5 * 60 * 1000;
-        private final Handler mHandler = new Handler();
-        private boolean mWebKitTimersAreSuspended = false;
-        private SuspendRunnable mSuspendRunnable;
-
-        private void onDestroy() {
-            if (mSuspendRunnable != null) {
-                mHandler.removeCallbacks(mSuspendRunnable);
-                mSuspendRunnable = null;
-            }
-        }
-
-        private void suspendTimers() {
-            if (mSuspendRunnable == null) {
-                mSuspendRunnable = new SuspendRunnable();
-                mHandler.postDelayed(mSuspendRunnable, SUSPEND_TIMERS_AFTER_MS);
-            }
-        }
-
-        private void startTimers() {
-            if (mSuspendRunnable != null) {
-                mHandler.removeCallbacks(mSuspendRunnable);
-                mSuspendRunnable = null;
-            } else if (mWebKitTimersAreSuspended) {
-                ContentViewStatics.setWebKitSharedTimersSuspended(false);
-                mWebKitTimersAreSuspended = false;
-            }
-        }
-    }
-
-    private final BackgroundProcessing mBackgroundProcessing = new BackgroundProcessing();
     private final PowerBroadcastReceiver mPowerBroadcastReceiver = new PowerBroadcastReceiver();
 
     // Used to trigger variation changes (such as seed fetches) upon application foregrounding.
     private VariationsSession mVariationsSession;
 
     private DevToolsServer mDevToolsServer;
 
     private boolean mIsStarted;
     private boolean mInitializedSharedClasses;
     private boolean mIsProcessInitialized;
@@ skipping 81 matching lines @@
 
     /**
      * Called when a top-level Chrome activity (ChromeTabbedActivity, FullscreenActivity) is
      * started in foreground. It will not be called again when other Chrome activities take over
      * (see onStart()), that is, when correct activity calls startActivity() for another Chrome
      * activity.
      */
     private void onForegroundSessionStart() {
         UmaUtils.recordForegroundStartTime();
         ChildProcessLauncher.onBroughtToForeground();
-        mBackgroundProcessing.startTimers();
         updatePasswordEchoState();
         FontSizePrefs.getInstance(this).onSystemFontScaleChanged();
         updateAcceptLanguages();
         mVariationsSession.start(getApplicationContext());
         mPowerBroadcastReceiver.onForegroundSessionStart();
 
         // Track the ratio of Chrome startups that are caused by notification clicks.
         // TODO(johnme): Add other reasons (and switch to recordEnumeratedHistogram).
         RecordHistogram.recordBooleanHistogram(
                 "Startup.BringToForegroundReason",
                 NotificationPlatformBridge.wasNotificationRecentlyClicked());
     }
 
     /**
      * Called when last of Chrome activities is stopped, ending the foreground session. This will
      * not be called when a Chrome activity is stopped because another Chrome activity takes over.
      * This is ensured by ActivityStatus, which switches to track new activity when its started and
      * will not report the old one being stopped (see createStateListener() below).
      */
     private void onForegroundSessionEnd() {
         if (!mIsStarted) return;
-        mBackgroundProcessing.suspendTimers();
         flushPersistentData();
         mIsStarted = false;
         mPowerBroadcastReceiver.onForegroundSessionEnd();
 
         ChildProcessLauncher.onSentToBackground();
         IntentHandler.clearPendingReferrer();
         IntentHandler.clearPendingIncognitoUrl();
 
         int totalTabCount = 0;
         for (WeakReference<Activity> reference : ApplicationStatus.getRunningActivities()) {
@@ skipping 10 matching lines @@
                 "Tab.TotalTabCount.BeforeLeavingApp", totalTabCount);
     }
 
     /**
      * Called after onForegroundSessionEnd() indicating that the activity whose onStop() ended the
      * last foreground session was destroyed.
      */
     private void onForegroundActivityDestroyed() {
         if (ApplicationStatus.isEveryActivityDestroyed()) {
             // These will all be re-initialized when a new Activity starts / upon next use.
-            mBackgroundProcessing.onDestroy();
             PartnerBrowserCustomizations.destroy();
             ShareHelper.clearSharedImages(this);
         }
     }
 
     private ApplicationStateListener createApplicationStateListener() {
         return new ApplicationStateListener() {
             @Override
             public void onApplicationStateChange(int newState) {
                 if (newState == ApplicationState.HAS_STOPPED_ACTIVITIES) {
@@ skipping 523 matching lines @@
      * Caches flags that are needed by Activities that launch before the native library is loaded
      * and stores them in SharedPreferences. Because this function is called during launch after the
      * library has loaded, they won't affect the next launch until Chrome is restarted.
      */
     private void cacheNativeFlags() {
         if (sIsFinishedCachingNativeFlags) return;
         FeatureUtilities.cacheNativeFlags(this);
         sIsFinishedCachingNativeFlags = true;
     }
 }