Merge pull request #11992 from protocolbuffers/deannagarcia-patch-2

Add plugin.proto to the list of well known files for python

python/BUILD.bazel

@@ -56,6 +56,7 @@ internal_copy_files(
     srcs = [
         "//:well_known_type_protos",
         "//src/google/protobuf:descriptor_proto_srcs",
+        "//src/google/protobuf/compiler:plugin.proto",
     ],
     strip_prefix = "src",
 )

src/google/protobuf/compiler/BUILD.bazel

@@ -208,7 +208,10 @@ filegroup(
 
 exports_files(
     srcs = ["plugin.proto"],
-    visibility = ["//:__pkg__"],
+    visibility = [
+        "//:__pkg__",
+        "//python:__pkg__",
+    ],
 )
 
 cc_library(