[CustomTabs] Report the navigation start as absolute time

base/BUILD.gn

Index: base/BUILD.gn
diff --git a/base/BUILD.gn b/base/BUILD.gn
index 3eef54e07ad8cd5ebafe5830235b7be77fc9ca8c..20a2a4207e8cce4b96b26f0f5ee9afb6bd0604cd 100644
--- a/base/BUILD.gn
+++ b/base/BUILD.gn
@@ -212,6 +212,8 @@ component("base") {
     "android/statistics_recorder_android.h",
     "android/sys_utils.cc",
     "android/sys_utils.h",
+    "android/time_utils.cc",
+    "android/time_utils.h",
     "android/trace_event_binding.cc",
     "android/trace_event_binding.h",
     "android/unguessable_token_android.cc",
@@ -2253,6 +2255,7 @@ if (is_android) {
       "android/java/src/org/chromium/base/SysUtils.java",
       "android/java/src/org/chromium/base/SystemMessageHandler.java",
       "android/java/src/org/chromium/base/ThreadUtils.java",
+      "android/java/src/org/chromium/base/TimeUtils.java",
       "android/java/src/org/chromium/base/TraceEvent.java",
       "android/java/src/org/chromium/base/UnguessableToken.java",
       "android/java/src/org/chromium/base/library_loader/LibraryLoader.java",
@@ -2327,6 +2330,7 @@ if (is_android) {
       "android/java/src/org/chromium/base/SysUtils.java",
       "android/java/src/org/chromium/base/SystemMessageHandler.java",
       "android/java/src/org/chromium/base/ThreadUtils.java",
+      "android/java/src/org/chromium/base/TimeUtils.java",
       "android/java/src/org/chromium/base/TraceEvent.java",
       "android/java/src/org/chromium/base/UnguessableToken.java",
       "android/java/src/org/chromium/base/VisibleForTesting.java",