Include external touchscreen vid/pid in UMA hardware profile

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 65 matching lines @@
     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;
   }
   optional OS os = 5;
 
-  // Next tag for Hardware: 14
+  // Next tag for Hardware: 16
   // 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;
 
     // The base memory address that chrome.dll was loaded at.
     // (Logged only on Windows.)
@@ skipping 115 matching lines @@
         // Product ID of the device, where available.
         optional uint32 product_id = 6;
 
         // Device ID of the device, generally the release or version number in
         // BCD format, where available.
         optional uint32 device_id = 7;
       }
       repeated PairedDevice paired_device = 3;
     }
     optional Bluetooth bluetooth = 11;
+
+    // Whether the internal display produces touch events.

[Alexei Svitkine (slow), 2014/02/04 21:13:35]

Expand comment to mention that if this is omitted if the value is unknown. Also,
both this comment and the comments below should mention that this is only
recorded on ChromeOS.

[tdresser, 2014/02/04 22:01:49]

Done. I'll land the google3 side of this change once this has landed.

+    optional bool internal_display_supports_touch = 14;
+
+    // Vendor ids and product ids of external touchscreens.
+    message TouchScreen {
+      // Touch screen vendor id.
+      optional uint32 vendor_id = 1;
+      // Touch screen product id.
+      optional uint32 product_id = 2;
+    }
+    // Lists vendor and product ids of external touchscreens.
+    repeated TouchScreen external_touchscreen = 15;
   }
   optional Hardware hardware = 6;
 
   // Information about the network connection.
   message Network {
     // Set to true if connection_type changed during the lifetime of the log.
     optional bool connection_type_is_ambiguous = 1;
 
     // See net::NetworkChangeNotifier::ConnectionType.
     enum ConnectionType {
@@ skipping 204 matching lines @@
     // Currently, the identifier is a hash of the group's name.
     optional fixed32 group_id = 2;
   }
   repeated FieldTrial field_trial = 9;
 
   // Number of users currently signed into a multiprofile session.
   // A zero value indicates that the user count changed while the log is open.
   // Logged only on ChromeOS.
   optional uint32 multi_profile_user_count = 17;
 }