formatter: populate ctx from repo and node value This will basically replace the fm.contexthint() API. I originally thought this would be too complicated, and I wrote 8399438bc7ef "formatter: provide hint of context keys required by template" because of that. However, I had to add a similar mechanism for fctx templates, and the overall machinery became way simpler than my original patch. The test output slightly changed as {author} is no longer available in the {manifest} context, which isn't the point this test targeted on.

--- a/tests/test-template-map.t
+++ b/tests/test-template-map.t
@@ -1756,5 +1756,5 @@
 
   $ hg -R latesttag log -r tip --style=style1989
   M|test
-  11,test
+  11,
   branch: test