Migrate diff to devtools_entrypoint

Bug: 1101738
Change-Id: Ib3010eee41e0ab1961753cd61afbdc208dbc003e
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/2312680
Commit-Queue: Jack Franklin <[email protected]>
Reviewed-by: Paul Lewis <[email protected]>
diff --git a/front_end/BUILD.gn b/front_end/BUILD.gn
index 624b509..403e2a5 100644
--- a/front_end/BUILD.gn
+++ b/front_end/BUILD.gn
@@ -15,6 +15,7 @@
     "common:bundle",
     "component_docs",
     "data_grid:bundle",
+    "diff:bundle",
     "dom_extension:bundle",
     "elements:bundle",
     "formatter:bundle",