bluetooth: Blink-side implementation of getCharacteristic.

Source/modules/bluetooth/BluetoothGATTCharacteristic.idl

Index: Source/modules/bluetooth/BluetoothGATTCharacteristic.idl
diff --git a/Source/modules/bluetooth/BluetoothGATTCharacteristic.idl b/Source/modules/bluetooth/BluetoothGATTCharacteristic.idl
index d90c23569ff72509a6259f81af483f81d2676ee5..2aed3712d7b1190d3cfe6c4bcec21024265fd3f7 100644
--- a/Source/modules/bluetooth/BluetoothGATTCharacteristic.idl
+++ b/Source/modules/bluetooth/BluetoothGATTCharacteristic.idl
@@ -11,8 +11,10 @@ typedef DOMString UUID;
     GarbageCollected,
     RuntimeEnabled=WebBluetooth,
 ] interface BluetoothGATTCharacteristic {//: CharacteristicEventHandlers {
+    // TODO(ortuno): Add test to make sure service matches the service
+    // used to call getCharacteristic.
     // readonly    attribute BluetoothGATTService     service;
-    // readonly    attribute UUID                     uuid;
+    readonly    attribute UUID                     uuid;
     // readonly    attribute CharacteristicProperties properties;
     // readonly    attribute ArrayBuffer?             value;
     // Promise<BluetoothGATTDescriptor>           getDescriptor(BluetoothDescriptorUUID descriptor);