metrics: Protobuf supports profiling upon restoring session

components/metrics/proto/sampled_profile.proto

 // Copyright 2014 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.
 
 syntax = "proto2";
 
 option optimize_for = LITE_RUNTIME;
 
 package metrics;
 
 import "perf_data.proto";
 
 // Protocol buffer for collected sample-based profiling data.
 // Contains the parameters and data from a single profile collection event.
 
-// Next tag: 7
+// Next tag: 9
 message SampledProfile {
   // Indicates the event that triggered this collection.
   enum TriggerEvent {
     UNKNOWN_TRIGGER_EVENT = 0;
 
     // The profile was triggered by periodic sampling.  Periodically sampled
     // profiles are collected once per uniformly sized period interval.  Within
     // each interval, the sampled data is collected at a random time.  For
     // example, if the interval is 60 s, then data would be collected at a
     // random point in each of the intervals [0, 60 s), [60 s, 120 s), etc.
     PERIODIC_COLLECTION = 1;
 
     // The profile was collected upon resume from suspend.
     RESUME_FROM_SUSPEND = 2;
+
+    // The profile was collected upon restoring a previous session.
+    RESTORE_SESSION = 3;
   }
   optional TriggerEvent trigger_event = 1;
 
   // Fields 2-3: Time durations are given in ticks, and represent system uptime
   // rather than wall time.
 
   // Time after system boot when the collection took place, in milliseconds.
   optional int64 ms_after_boot = 2;
 
   // Time after last login when the collection took place, in milliseconds.
   optional int64 ms_after_login = 3;
 
   // The duration for which the machine was suspended prior to collecting the
   // sampled profile. Only set when |trigger_event| is RESUME_FROM_SUSPEND.
   optional int64 suspend_duration_ms = 5;
 
   // Number of milliseconds after a resume that profile was collected. Only set
   // when |trigger_event| is RESUME_FROM_SUSPEND.
   optional int64 ms_after_resume = 6;
 
+  // Number of tabs restored during a session restore. Only set when
+  // |trigger_event| is RESTORE_SESSION.
+  optional int32 num_tabs_restored = 7;
+
+  // Number of milliseconds after a session restore that a profile was
+  // collected. Only set when |trigger_event| is RESTORE_SESSION.
+  optional int64 ms_after_restore = 8;
+
   // The actual perf data that was collected.
   optional PerfDataProto perf_data = 4;
 }