replace catch+throw with finally !ok, to get rid of UnhandledExceptio…

…n shown as error

method declared as throwing only IOException, but unchecked exceptions can always happen

usbSerialForAndroid/src/main/java/com/hoho/android/usbserial/driver/CommonUsbSerialPort.java

@@ -117,18 +117,21 @@ public void open(UsbDeviceConnection connection) throws IOException {
             throw new IllegalArgumentException("Connection is null");
         }
         mConnection = connection;
+        boolean ok = false;
         try {
             openInt();
             if (mReadEndpoint == null || mWriteEndpoint == null) {
                 throw new IOException("Could not get read & write endpoints");
             }
             mUsbRequest = new UsbRequest();
             mUsbRequest.initialize(mConnection, mReadEndpoint);
-        } catch(Exception e) {
-            try {
-                close();
-            } catch(Exception ignored) {}
-            throw e;
+            ok = true;
+        } finally {
+            if (!ok) {
+                try {
+                    close();
+                } catch (Exception ignored) {}
+            }
         }
     }