bluetooth: Add characteristic list to DeviceDetailsPage in internals page.

device/bluetooth/public/interfaces/device.mojom

Index: device/bluetooth/public/interfaces/device.mojom
diff --git a/device/bluetooth/public/interfaces/device.mojom b/device/bluetooth/public/interfaces/device.mojom
index 71922af2439e8515f4db175fa1991cecaa06a992..5fb82e52dd654c7b16ad8da17a0469bf943441eb 100644
--- a/device/bluetooth/public/interfaces/device.mojom
+++ b/device/bluetooth/public/interfaces/device.mojom
@@ -25,6 +25,29 @@ struct ServiceInfo {
   bool is_primary;
 };
 
+struct Properties {
+  bool broadcast;
+  bool read;
+  bool write_without_response;
+  bool write;
+  bool notify;
+  bool indicate;
+  bool authenticated_signed_writes;
+  bool extended_properties;
+  bool reliable_write;
+  bool writable_auxiliaries;
+  bool read_encrypted;
+  bool write_encrypted;
+  bool read_encrypted_authenticated;
+  bool write_encrypted_authenticated;
+};
+
+struct CharacteristicInfo {
+  string id;
+  UUID uuid;
+  Properties properties;
+};
+
 interface Device {
   // Disconnects and deletes the Device.
   Disconnect();
@@ -35,4 +58,8 @@ interface Device {
 
   // Gets the GATT Services in this device's GATT Server.
   GetServices() => (array<ServiceInfo> services);
+
+  // Gets the GATT Characteristics in the GATT Service with |service_id|.
+  GetCharacteristics(string service_id) =>
+      (array<CharacteristicInfo> characteristics);
 };