add a check for existing package.json file

Author: vtrifonov

test-app/build-tools/static-binding-generator/src/main/java/org/nativescript/staticbindinggenerator/Main.java

@@ -68,6 +68,9 @@ private static void generateJsInputFile() throws IOException {
 
     private static boolean isSuppressCallJSMethodExceptionsEnabled() throws IOException{
         File jsonFile = new File(inputDir, "package.json");
+        if (!jsonFile.exists()) {
+            return false;
+        }
         String jsonContent = FileUtils.readFileToString(jsonFile, "UTF-8");
         JSONObject pjson = null;
         try {