Increase Web Bluetooth device scanning duration [merge to M56]

content/browser/bluetooth/bluetooth_device_chooser_controller.h

Index: content/browser/bluetooth/bluetooth_device_chooser_controller.h
diff --git a/content/browser/bluetooth/bluetooth_device_chooser_controller.h b/content/browser/bluetooth/bluetooth_device_chooser_controller.h
index 0922d7e31b4288dac01944efda91f010dd6f8739..685cf89a6a1c8738ef6a24dfab28829dadc0340f 100644
--- a/content/browser/bluetooth/bluetooth_device_chooser_controller.h
+++ b/content/browser/bluetooth/bluetooth_device_chooser_controller.h
@@ -8,6 +8,7 @@
 #include <string>
 
 #include "base/memory/weak_ptr.h"
+#include "base/optional.h"
 #include "base/time/time.h"
 #include "base/timer/timer.h"
 #include "content/common/content_export.h"
@@ -145,6 +146,9 @@ class CONTENT_EXPORT BluetoothDeviceChooserController final {
   // http://crbug.com/611852
   std::unique_ptr<device::BluetoothDiscoverySession> discovery_session_;
 
+  // The time when scanning starts.
+  base::Optional<base::TimeTicks> scanning_start_time_;
+
   // Weak pointer factory for generating 'this' pointers that might live longer
   // than we do.
   // Note: This should remain the last member so it'll be destroyed and