title: Samsung S7 (Oreo) BLE scan and disconnect problems
body: <p>Our app needs to connect with BLE device to collecting data, the code has two problems when running on Samsung S7 (model name SM-930W8, Android 8.0): </p>
  
  <ol>
  <li>BluetoothLeScanner.startScan(filters, settings, mScanCallback) fails to find our device (can be solved if we passes an empty filters and filter by our code later on); </li>
  <li>BluetoothGatt.disconnect() will not disconnect with Samsung S7 with our device. We use compileSdkVersion 29, minSdkVersion 26.
  This app works on Samsung S7 Active, Samsung S8 (SM-G950W), also works on Samsung S6 Edge if downgrade the minSdkVersion to 24. I also tried to turn off 'Nearby device scanning' on Samsung S7, did not work. </li>
  </ol>
  
  <pre><code>ScanSettings settings = new ScanSettings.Builder()
                  .setScanMode(ScanSettings.SCAN_MODE_LOW_LATENCY)
                  .build();
  mBluetoothLeScanner.startScan(filters, settings, mScanCallback);
  </code></pre>
  
  <pre><code>mGatt.disconnect();
  </code></pre>