Support embedded plugins with MimeHandlerView.

chrome/browser/extensions/plugin_manager.cc

Index: chrome/browser/extensions/plugin_manager.cc
diff --git a/chrome/browser/extensions/plugin_manager.cc b/chrome/browser/extensions/plugin_manager.cc
index 8d979f2fa8a1ca99c06a91375a3622cf58f7e7bc..3f6a8575bd1f5623e4821eeded434a01d3f1cc2f 100644
--- a/chrome/browser/extensions/plugin_manager.cc
+++ b/chrome/browser/extensions/plugin_manager.cc
@@ -97,6 +97,11 @@ void PluginManager::OnExtensionLoaded(content::BrowserContext* browser_context,
          mime_type != handler->mime_type_set().end(); ++mime_type) {
       content::WebPluginMimeType mime_type_info;
       mime_type_info.mime_type = *mime_type;
+      base::FilePath::StringType file_extension;
+      if (net::GetPreferredExtensionForMimeType(*mime_type, &file_extension)) {
+        mime_type_info.file_extensions.push_back(
+            base::FilePath(file_extension).AsUTF8Unsafe());
+      }
       info.mime_types.push_back(mime_type_info);
     }