bluetooth: Refactor GetDescriptorForUUID to GetDescriptorsForUUID.

device/bluetooth/android/java/src/org/chromium/device/bluetooth/ChromeBluetoothRemoteGattCharacteristic.java

Index: device/bluetooth/android/java/src/org/chromium/device/bluetooth/ChromeBluetoothRemoteGattCharacteristic.java
diff --git a/device/bluetooth/android/java/src/org/chromium/device/bluetooth/ChromeBluetoothRemoteGattCharacteristic.java b/device/bluetooth/android/java/src/org/chromium/device/bluetooth/ChromeBluetoothRemoteGattCharacteristic.java
index 6d19c1f5c164b998025f236e11cb78d87cae0cf9..70d8e8eaf885c0b6f1aba07136bf9464246b594a 100644
--- a/device/bluetooth/android/java/src/org/chromium/device/bluetooth/ChromeBluetoothRemoteGattCharacteristic.java
+++ b/device/bluetooth/android/java/src/org/chromium/device/bluetooth/ChromeBluetoothRemoteGattCharacteristic.java
@@ -148,10 +148,14 @@ final class ChromeBluetoothRemoteGattCharacteristic {
     private void createDescriptors() {
         List<Wrappers.BluetoothGattDescriptorWrapper> descriptors =
                 mCharacteristic.getDescriptors();
+        // descriptorInstanceId ensures duplicate UUIDs have unique instance
+        // IDs. BluetoothGattDescriptor does not offer getInstanceId the way
+        // BluetoothGattCharacteristic does.
+        //
+        // TODO(crbug.com/576906) Do not reuse IDs upon onServicesDiscovered.
+        int instanceIdCounter = 0;
         for (Wrappers.BluetoothGattDescriptorWrapper descriptor : descriptors) {
-            // Create an adapter unique descriptor ID.
-            // TODO(crbug.com/576900) Unique descriptorInstanceId duplicate UUID values.
-            String descriptorInstanceId = mInstanceId + "/" + descriptor.getUuid().toString();
+            String descriptorInstanceId = mInstanceId + "/" + instanceIdCounter++;

[ortuno, 2016/03/13 20:41:44]

Hmm I wonder if we should include the UUID. I think it will make it easier to
identify the descriptors in logs, but then we can just include the UUID in the
log anyway. Up to you.

[scheib, 2016/03/25 00:13:57]

Done: Including the UUID.

             nativeCreateGattRemoteDescriptor(mNativeBluetoothRemoteGattCharacteristicAndroid,
                     descriptorInstanceId, descriptor, mChromeDevice);
         }