Correct $ref links in extensions documentation server relative location.

chrome/common/extensions/docs/server2/intro_data_source.py

Index: chrome/common/extensions/docs/server2/intro_data_source.py
diff --git a/chrome/common/extensions/docs/server2/intro_data_source.py b/chrome/common/extensions/docs/server2/intro_data_source.py
index 161373414ab1ebb2983d8915188e4f73e6672ad0..d7a1a84dbb769903892aef55784ae600f3870569 100644
--- a/chrome/common/extensions/docs/server2/intro_data_source.py
+++ b/chrome/common/extensions/docs/server2/intro_data_source.py
@@ -95,7 +95,7 @@ class IntroDataSource(DataSource):
     # Guess the name of the API from the path to the intro.
     api_name = os.path.splitext(intro_path.split('/')[-1])[0]
     intro_with_links = self._ref_resolver.ResolveAllLinks(
-            intro, namespace=api_name)
+            intro, self._request, namespace=api_name)
 
     # TODO(kalman): In order to pick up every header tag, and therefore make a
     # complete TOC, the render context of the Handlebar needs to be passed