Add Android fingerprint to metrics logs

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;
@@ skipping 47 matching lines @@
   // e.g. "en-US".
   optional string application_locale = 4;
 
   // Information on the user's operating system.
   message OS {
     // The user's operating system.
     optional string name = 1;
 
     // The version of the OS.  The meaning of this field is OS-dependent.
     optional string version = 2;
+
+    // The fingerprint of the build.  This field is used only on Android.
+    optional string fingerprint = 3;

[Ilya Sherman, 2012/10/01 23:01:38]

How is this field going to be used?

   }
   optional OS os = 5;
 
   // Information on the user's hardware.
   message Hardware {
     // The CPU architecture (x86, PowerPC, x86_64, ...)
     optional string cpu_architecture = 1;
 
     // The amount of RAM present on the system, in megabytes.
     optional int64 system_ram_mb = 2;
@@ skipping 222 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;
 }