Include external touchscreen vid/pid in UMA hardware profile

chrome/browser/metrics/metrics_log.cc

Index: chrome/browser/metrics/metrics_log.cc
diff --git a/chrome/browser/metrics/metrics_log.cc b/chrome/browser/metrics/metrics_log.cc
index 9ebf3bc72e2dbe7c9e57ca7e3e8a4aade3a9e105..bcd0a18884c0493f005add20b7a6c2008726f771 100644
--- a/chrome/browser/metrics/metrics_log.cc
+++ b/chrome/browser/metrics/metrics_log.cc
@@ -66,6 +66,7 @@ extern "C" IMAGE_DOS_HEADER __ImageBase;
 
 #if defined(OS_CHROMEOS)
 #include "chrome/browser/chromeos/login/user_manager.h"
+#include "ui/events/x/touch_factory_x11.h"
 #endif
 
 using content::GpuDataManager;
@@ -372,6 +373,18 @@ PairedDevice::Type AsBluetoothDeviceType(
   NOTREACHED();
   return PairedDevice::DEVICE_UNKNOWN;
 }
+
+void WriteTouchscreensProto(SystemProfileProto::Hardware* hardware) {
+  std::set<std::pair<int, int> > touchscreen_ids =
+    ui::TouchFactory::GetInstance()->GetTouchscreenIds();
+  std::set<std::pair<int, int> >::iterator it;
+  for (it = touchscreen_ids.begin(); it != touchscreen_ids.end(); ++it) {
+    SystemProfileProto::Hardware::TouchScreen* touchscreen =
+        hardware->add_external_touchscreen();
+    touchscreen->set_vendor_id(it->first);
+    touchscreen->set_product_id(it->second);
+  }
+}
 #endif  // defined(OS_CHROMEOS)
 
 // Round a timestamp measured in seconds since epoch to one with a granularity
@@ -798,6 +811,7 @@ void MetricsLog::RecordEnvironment(
                  base::Unretained(this)));
   DCHECK(adapter_.get());
   WriteBluetoothProto(hardware);
+  WriteTouchscreensProto(hardware);
   UpdateMultiProfileUserCount();
 #endif