Move list of supported H264 codecs from InternalEncoderFactory to h264.h

This CL is a clean-up to prepare for adding more supported codecs for the internal H264 SW codec.

Bug: webrtc:8317
Change-Id: If483d05c01c40bbc81cbd1a6aad89961689714ef
Reviewed-on: https://webrtc-review.googlesource.com/4940
Reviewed-by: Sami Kalliomäki <sakal@webrtc.org>
Reviewed-by: Rasmus Brandt <brandtr@webrtc.org>
Commit-Queue: Magnus Jedvert <magjed@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#20105}
diff --git a/modules/video_coding/BUILD.gn b/modules/video_coding/BUILD.gn
index 785533a..452f0bf 100644
--- a/modules/video_coding/BUILD.gn
+++ b/modules/video_coding/BUILD.gn
@@ -188,6 +188,7 @@
   defines = []
   deps = [
     ":video_coding_utility",
+    "../../api/video_codecs:video_codecs_api",
     "../../media:rtc_media_base",
     "../../rtc_base:rtc_base_approved",
     "../../system_wrappers",