Split out foreground session tracking from the application code.

chrome/android/java/src/org/chromium/chrome/browser/init/ChromeLifetimeController.java

Index: chrome/android/java/src/org/chromium/chrome/browser/init/ChromeLifetimeController.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/ChromeLifetimeController.java b/chrome/android/java/src/org/chromium/chrome/browser/init/ChromeLifetimeController.java
similarity index 80%
rename from chrome/android/java/src/org/chromium/chrome/browser/ChromeLifetimeController.java
rename to chrome/android/java/src/org/chromium/chrome/browser/init/ChromeLifetimeController.java
index 3e013c9fd61324da61fa1f05ca99d1d10a15a485..de31bc2f69a1b103491c5aa9568357e0f1401f71 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/ChromeLifetimeController.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/init/ChromeLifetimeController.java
@@ -2,7 +2,7 @@
 // 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;
+package org.chromium.chrome.browser.init;
 
 import android.app.Activity;
 import android.content.Context;
@@ -12,6 +12,10 @@ import android.os.Process;
 import org.chromium.base.ActivityState;
 import org.chromium.base.ApplicationStatus;
 import org.chromium.base.ContextUtils;
+import org.chromium.base.ThreadUtils;
+import org.chromium.base.annotations.SuppressFBWarnings;
+import org.chromium.chrome.browser.ApplicationLifetime;
+import org.chromium.chrome.browser.BrowserRestartActivity;
 
 import java.lang.ref.WeakReference;
 
@@ -28,13 +32,24 @@ class ChromeLifetimeController implements ApplicationLifetime.Observer,
         ApplicationStatus.ActivityStateListener {
     private static final String TAG = "LifetimeController";
 
+    private static ChromeLifetimeController sInstance;
+
     private boolean mRestartChromeOnDestroy;
     private int mRemainingActivitiesCount = 0;
 
-    public ChromeLifetimeController() {
-        ApplicationLifetime.addObserver(this);
+    /**
+     * Initialize the ChromeLifetimeController;
+     */
+    @SuppressFBWarnings("LI_LAZY_INIT_UPDATE_STATIC")
+    public static void initialize() {
+        ThreadUtils.assertOnUiThread();
+        if (sInstance != null) return;
+        sInstance = new ChromeLifetimeController();
+        ApplicationLifetime.addObserver(sInstance);
     }
 
+    private ChromeLifetimeController() {}
+
     @Override
     public void onTerminate(boolean restart) {
         mRestartChromeOnDestroy = restart;