ImageService(save): use Throwables.propagate() from Guava.

Fixed PMD warning about throwing raw exception type.

No functional changes.

Author: php-coder

src/main/java/ru/mystamps/web/service/ImageService.java

@@ -27,6 +27,8 @@
 import org.springframework.transaction.annotation.Transactional;
 import org.springframework.web.multipart.MultipartFile;
 
+import  com.google.common.base.Throwables;
+
 import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Preconditions.checkState;
 
@@ -61,7 +63,7 @@ String save(final MultipartFile file) {
 			image.setImage(file.getBytes());
 		} catch (final IOException e) {
 			// throw RuntimeException for rolling back transaction
-			throw new RuntimeException(e);
+			throw Throwables.propagate(e);
 		}
 
 		final Image entity = imageDao.save(image);