added contenttype extension for response schema.

Author: HugoMario

src/main/java/io/swagger/codegen/v3/generators/DefaultCodegenConfig.java

@@ -3752,8 +3752,9 @@ protected Schema getSchemaFromResponse(ApiResponse response) {
             return null;
         }
         Schema schema = null;
-        for (MediaType mediaType : response.getContent().values()) {
-            schema = mediaType.getSchema();
+        for (String contentType : response.getContent().keySet()) {
+            schema = response.getContent().get(contentType).getSchema();
+            schema.addExtension("x-content-type", contentType);
             break;
         }
         return schema;

src/main/resources/handlebars/htmlDocs2/index.mustache

@@ -344,7 +344,7 @@
                                     <script>
                                       $(document).ready(function() {
                                         var schemaWrapper = {{{jsonSchema}}};
-                                        var schema = schemaWrapper.content["{{contentType}}"].schema;
+                                        var schema = schemaWrapper.content["{{extensions.x-content-type}}"].schema;
                                         if (schema.$ref != null) {
                                           schema = defsParser.$refs.get(schema.$ref);
                                         } else {

src/main/resources/mustache/htmlDocs2/index.mustache

@@ -344,7 +344,7 @@
                                     <script>
                                       $(document).ready(function() {
                                         var schemaWrapper = {{{jsonSchema}}};
-                                        var schema = schemaWrapper.content[{{contentType}}].schema;
+                                        var schema = schemaWrapper.content["{{extensions.x-content-type}}"].schema;
                                         var schema = schemaWrapper.schema;
                                         if (schema.$ref != null) {
                                           schema = defsParser.$refs.get(schema.$ref);