Add NetworkChangeNotifier::ConnectionType to SystemProfile.

chrome/common/metrics/proto/system_profile.proto

 // Copyright (c) 2012 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.
 //
 // Stores information about the user's brower and system configuration.
 // The system configuration fields are recorded once per client session.
 
 syntax = "proto2";
 
 option optimize_for = LITE_RUNTIME;
 
 package metrics;
 
-// Next tag: 12
+// Next tag: 13

[Ilya Sherman, 2013/01/26 00:49:00]

nit: Please bump this one further and use 13 for your tag to avoid conflicting
with https://chromiumcodereview.appspot.com/12036047/

[szym, 2013/01/28 18:16:25]

Done.

 message SystemProfileProto {
   // The time when the client was compiled/linked, in seconds since the epoch.
   optional int64 build_timestamp = 1;
 
   // A version number string for the application.
   // Most commonly this is the browser version number found in a user agent
   // string, and is typically a 4-tuple of numbers separated by periods.  In
   // cases where the user agent version might be ambiguous (example: Linux 64-
   // bit build, rather than 32-bit build, or a Windows version used in some
   // special context, such as ChromeFrame running in IE), then this may include
@@ skipping 115 matching lines @@
       optional string gl_vendor = 6;
       
       // The GL_RENDERER string. An example of a gl_renderer string is 
       // "PowerVR SGX 540". "" if we are not using OpenGL.
       optional string gl_renderer = 7;
     }
     optional Graphics gpu = 8;
   }
   optional Hardware hardware = 6;
 
+  // Information about the network connection.
+  message Network {
+    // Set to true if there was a network change during the lifetime of the log.
+    optional bool is_ambiguous = 1;

[Ilya Sherman, 2013/01/26 00:49:00]

nit: Perhaps name this "connection_type_is_ambiguous"?  Or is this likely to
affect any new fields that get added to this message as well?

[szym, 2013/01/28 18:16:25]

Good point. I wanted to have one such flag for all of Network{}, but once we add
gateway OUI or wifi PHY mode (a/b/g/n), there's the opportunity to have specific
connection_type while the other details are ambiguous.

Done.

+
+    // See net::NetworkChangeNotifier::ConnectionType.

[Ilya Sherman, 2013/01/26 00:49:00]

nit: IMO it would be better to copy the short comment from there, rather than
pointing to that comment from here.

[szym, 2013/01/28 18:16:25]

That link in that other comment is out of date. The current version of
netinfo-api (http://www.w3.org/TR/2012/WD-netinfo-api-20121129/) prefers
"bandwidth" instead of discrete types
(http://www.w3.org/TR/2011/WD-netinfo-api-20110607/).

With this concern, I think it's best to refer what is actually being recorded
here.

+    enum ConnectionType {
+      CONNECTION_UNKNOWN = 0;
+      CONNECTION_ETHERNET = 1;
+      CONNECTION_WIFI = 2;
+      CONNECTION_2G = 3;
+      CONNECTION_3G = 4;
+      CONNECTION_4G = 5;
+    }
+    optional ConnectionType connection_type = 2;
+  }
+  optional Network network = 12;
+
   // Information on the Google Update install that is managing this client.
   message GoogleUpdate {
     // Whether the Google Update install is system-level or user-level.
     optional bool is_system_install = 1;
 
     // The date at which Google Update last started performing an automatic
     // update check, in seconds since the Unix epoch.
     optional int64 last_automatic_start_timestamp = 2;
 
     // The date at which Google Update last successfully sent an update check
@@ skipping 158 matching lines @@
     // The name of the field trial, as a 32-bit identifier.
     // Currently, the identifier is a hash of the field trial's name.
     optional fixed32 name_id = 1;
 
     // The user's group within the field trial, as a 32-bit identifier.
     // Currently, the identifier is a hash of the group's name.
     optional fixed32 group_id = 2;
   }
   repeated FieldTrial field_trial = 9;
 }