Separate deferred startup into tasks.

chrome/android/java/src/org/chromium/chrome/browser/metrics/UmaUtils.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.metrics;
 
 import android.os.SystemClock;
 
 import org.chromium.base.annotations.CalledByNative;
 import org.chromium.base.annotations.JNINamespace;
 
 /**
  * Utilities to support startup metrics - Android version.
  */
 @JNINamespace("chrome::android")
 public class UmaUtils {
     private static long sApplicationStartWallClockMs;
     private static long sApplicationStartUptimeMs;
 
     private static boolean sRunningApplicationStart;
+    private static long sForegroundStartTimeMs;
 
     /**
      * Record the time at which the activity started. This should be called asap after
      * the start of the activity's onCreate function.
      */
     public static void recordMainEntryPointTime() {
         // We can't simply pass this down through a JNI call, since the JNI for chrome
         // isn't initialized until we start the native content browser component, and we
         // then need the start time in the C++ side before we return to Java. As such we
         // save it in a static that the C++ can fetch once it has initialized the JNI.
         sApplicationStartWallClockMs = System.currentTimeMillis();
         sApplicationStartUptimeMs = SystemClock.uptimeMillis();
     }
 
+    public static void recordForegroundStartTime() {
+        sForegroundStartTimeMs = SystemClock.uptimeMillis();
+    }
+
     /**
      * Whether the application is in the early stage since the browser process start. The
      * "application start" ends right after the last histogram related to browser startup is
      * recorded. Currently, the very first navigation commit in the lifetime of the process ends the
      * "application start".
      * Must only be called on the UI thread.
      */
     public static boolean isRunningApplicationStart() {
         return sRunningApplicationStart;
     }
@@ skipping 14 matching lines @@
     public static void recordMetricsReportingDefaultOptIn(boolean optIn) {
         nativeRecordMetricsReportingDefaultOptIn(optIn);
     }
 
     @CalledByNative
     public static long getMainEntryPointWallTime() {
         return sApplicationStartWallClockMs;
     }
 
     public static long getMainEntryPointTime() {
         return sApplicationStartUptimeMs;

[Yaron, 2016/07/06 14:27:50]

so remove this now?

[Peter Wen, 2016/07/06 15:21:37]

Done.

     }
 
+    public static long getForegroundStartTime() {
+        assert sForegroundStartTimeMs != 0;
+        return sForegroundStartTimeMs;
+    }
+
     private static native void nativeRecordMetricsReportingDefaultOptIn(boolean optIn);
 }