[CustomTabs] Report the navigation start as absolute time

chrome/android/java/src/org/chromium/chrome/browser/customtabs/CustomTabsConnection.java

Index: chrome/android/java/src/org/chromium/chrome/browser/customtabs/CustomTabsConnection.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/customtabs/CustomTabsConnection.java b/chrome/android/java/src/org/chromium/chrome/browser/customtabs/CustomTabsConnection.java
index f2694e7627cb265a30ad6f42815e97692579968c..1088ec594798386dc7b413316155707a90b5c06c 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/customtabs/CustomTabsConnection.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/customtabs/CustomTabsConnection.java
@@ -40,6 +40,7 @@ import org.chromium.chrome.browser.IntentHandler;
 import org.chromium.chrome.browser.WarmupManager;
 import org.chromium.chrome.browser.device.DeviceClassManager;
 import org.chromium.chrome.browser.init.ChromeBrowserInitializer;
+import org.chromium.chrome.browser.metrics.PageLoadMetrics;
 import org.chromium.chrome.browser.net.spdyproxy.DataReductionProxySettings;
 import org.chromium.chrome.browser.preferences.PrefServiceBridge;
 import org.chromium.chrome.browser.prerender.ExternalPrerenderHandler;
@@ -613,12 +614,16 @@ public class CustomTabsConnection {
      *
      * @param session Session identifier.
      * @param metricName Name of the page load metric.
+     * @param navigationStartMs Absolute navigation start time, in milliseconds since system boot
+     * time. Can be compared with times returned by SystemClock.uptimeMillis().
      * @param offsetMs Offset in ms from navigationStart.
      */
-    boolean notifyPageLoadMetric(CustomTabsSessionToken session, String metricName, long offsetMs) {
+    boolean notifyPageLoadMetric(CustomTabsSessionToken session, String metricName,
+            long navigationStartMs, long offsetMs) {
         CustomTabsCallback callback = mClientManager.getCallbackForSession(session);
         if (callback == null) return false;
         Bundle args = new Bundle();
+        args.putLong(PageLoadMetrics.NAVIGATION_START, navigationStartMs);
         args.putLong(metricName, offsetMs);
         try {
             callback.extraCallback(PAGE_LOAD_METRICS_CALLBACK, args);