Fixed crash on API < 16

src/acr/browser/lightning/LightningView.java

@@ -82,9 +82,9 @@ public class LightningView {
 		mWebView.setAnimationCacheEnabled(false);
 		mWebView.setDrawingCacheEnabled(true);
 		mWebView.setBackgroundColor(activity.getResources().getColor(android.R.color.white));
-		mWebView.setBackground(null);
 
 		if (API > 15) {
+			mWebView.setBackground(null);
 			mWebView.getRootView().setBackground(null);
 		} else {
 			mWebView.getRootView().setBackgroundDrawable(null);