Stop using //third_party/protobuf/3.6.1 in //src

Closes #10648.

PiperOrigin-RevId: 293565428
diff --git a/src/main/java/com/google/devtools/build/lib/analysis/platform/BUILD b/src/main/java/com/google/devtools/build/lib/analysis/platform/BUILD
index a8ec4e5..ec4059f 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/platform/BUILD
+++ b/src/main/java/com/google/devtools/build/lib/analysis/platform/BUILD
@@ -40,7 +40,7 @@
         "//src/main/java/com/google/devtools/build/lib/actions",
         "//src/main/java/com/google/devtools/build/lib/remote/options",
         "//third_party:guava",
-        "//third_party/protobuf/3.6.1:protobuf_java",
+        "//third_party/protobuf:protobuf_java",
         "@remoteapis//:build_bazel_remote_execution_v2_remote_execution_java_proto",
     ],
 )
diff --git a/src/main/protobuf/BUILD b/src/main/protobuf/BUILD
index 9315755..4caa503 100644
--- a/src/main/protobuf/BUILD
+++ b/src/main/protobuf/BUILD
@@ -1,10 +1,10 @@
+load("@com_google_protobuf//:protobuf.bzl", "py_proto_library")
+load("@rules_cc//cc:defs.bzl", "cc_proto_library")
 load("@rules_java//java:defs.bzl", "java_proto_library")
-load("//tools/build_rules:utilities.bzl", "java_library_srcs")
-load("//third_party/protobuf/3.6.1:protobuf.bzl", "py_proto_library")
+load("@rules_proto//proto:defs.bzl", "proto_library")
 load("//third_party/grpc:build_defs.bzl", "java_grpc_library")
 load("//third_party/grpc/bazel:cc_grpc_library.bzl", "cc_grpc_library")
-load("@rules_cc//cc:defs.bzl", "cc_proto_library")
-load("@rules_proto//proto:defs.bzl", "proto_library")
+load("//tools/build_rules:utilities.bzl", "java_library_srcs")
 
 package(default_visibility = ["//visibility:public"])