Forward MIME types to BrowserPlugin when a viewer is specified.

chrome/common/extensions/manifest_handlers/mime_types_handler.h

Index: chrome/common/extensions/manifest_handlers/mime_types_handler.h
diff --git a/chrome/common/extensions/manifest_handlers/mime_types_handler.h b/chrome/common/extensions/manifest_handlers/mime_types_handler.h
index 84e049f9d7c1c5a2a0f2942c0832fe55208e7453..0ee47ccbe3fe5985a51dfed56a7a943094b82210 100644
--- a/chrome/common/extensions/manifest_handlers/mime_types_handler.h
+++ b/chrome/common/extensions/manifest_handlers/mime_types_handler.h
@@ -41,6 +41,8 @@ class MimeTypesHandler {
   // The URL that will be used to handle MIME type requests.
   const std::string handler_url() const { return handler_url_; }
 
+  const std::set<std::string>& mime_type_set() const { return mime_type_set_; }
+
  private:
   // The id for the extension this action belongs to (as defined in the
   // extension manifest).