Fix Bluetooth enable dialog to match Android style guide.

When an app requests to enable Bluetooth and/or Bluetooth discovery,
we show a dialog for user confirmation. Remove the dialog title,
update the message text and button labels to be more descriptive,
and use the standard dialog layout instead of a custom layout.

Also fixes the button layout on the Bluetooth permission test app so
that the "Discoverable" button doesn't wrap to two lines.

Bug: 6001468
Change-Id: I731e2f31b4c822395fc3f83584a092550d9ae7d3

tests/src/com/android/settings/tests/BluetoothRequestPermissionTest.java

@@ -36,6 +36,9 @@ public class BluetoothRequestPermissionTest extends Activity {
     BluetoothAdapter mAdapter;
     private ArrayAdapter<String> mMsgAdapter;
 
+    // Discoverable button alternates between 20 second timeout and no timeout.
+    private boolean mDiscoveryWithTimeout = true;
+
     private class BtOnClickListener implements OnClickListener {
         final boolean mEnableOnly; // enable or enable + discoverable
 
@@ -103,7 +106,10 @@ public class BluetoothRequestPermissionTest extends Activity {
         } else {
             addMsg("Starting activity to enable bt + discovery");
             i.setAction(BluetoothAdapter.ACTION_REQUEST_DISCOVERABLE);
-            i.putExtra(BluetoothAdapter.EXTRA_DISCOVERABLE_DURATION, 20);
+            // Discoverability duration toggles between 20 seconds and no timeout.
+            int timeout = (mDiscoveryWithTimeout ? 20 : 0);
+            i.putExtra(BluetoothAdapter.EXTRA_DISCOVERABLE_DURATION, timeout);
+            mDiscoveryWithTimeout = !mDiscoveryWithTimeout;
         }
         startActivityForResult(i, 1);
     }