Add SubRunContainer to public.bzl

Missed this particular build in "Move SubRunContainer to its own .h
and .cpp" [0][1].

[0] https://skia-review.googlesource.com/c/skia/+/545776
[1] d881def3e544be7db5524a80e5dce7ca0a970f09

Change-Id: Icabef047b5397d1ba29237ecdd3e2dfa39e43205
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/546111
Reviewed-by: Kevin Lubick <kjlubick@google.com>

public.bzl

diff --git a/public.bzl b/public.bzl
index 398978a..80c76ff 100644
--- a/public.bzl
+++ b/public.bzl
@@ -1651,6 +1651,8 @@
     "src/text/gpu/StrikeCache.h",
     "src/text/gpu/SubRunAllocator.cpp",
     "src/text/gpu/SubRunAllocator.h",
+    "src/text/gpu/SubRunContainer.cpp",
+    "src/text/gpu/SubRunContainer.h",
     "src/text/gpu/TextBlob.cpp",
     "src/text/gpu/TextBlob.h",
     "src/text/gpu/TextBlobRedrawCoordinator.cpp",