update third_party/protobuf to 3.11.4

bazel/grpc_deps.bzl

@@ -154,11 +154,11 @@ def grpc_deps():
     if "com_google_protobuf" not in native.existing_rules():
         http_archive(
             name = "com_google_protobuf",
-            sha256 = "51398b0b97b353c1c226d0ade0bae80c80380e691cba7c1a108918986784a1c7",
-            strip_prefix = "protobuf-29cd005ce1fe1a8fabf11e325cb13006a6646d59",
+            sha256 = "2435b7fb83b8a608c24ca677907aa9a35e482a7f018e65ca69481b3c8c9f7caf",
+            strip_prefix = "protobuf-d0bfd5221182da1a7cc280f3337b5e41a89539cf",
             urls = [
-                "https://storage.googleapis.com/grpc-bazel-mirror/github.com/google/protobuf/archive/29cd005ce1fe1a8fabf11e325cb13006a6646d59.tar.gz",
-                "https://github.com/google/protobuf/archive/29cd005ce1fe1a8fabf11e325cb13006a6646d59.tar.gz",
+                "https://storage.googleapis.com/grpc-bazel-mirror/github.com/google/protobuf/archive/d0bfd5221182da1a7cc280f3337b5e41a89539cf.tar.gz",
+                "https://github.com/google/protobuf/archive/d0bfd5221182da1a7cc280f3337b5e41a89539cf.tar.gz",
             ],
         )
 

third_party/protobuf

@@ -1 +1 @@
-Subproject commit fe1790ca0df67173702f70d5646b82f48f412b99
+Subproject commit d0bfd5221182da1a7cc280f3337b5e41a89539cf

tools/run_tests/sanity/check_submodules.sh

@@ -36,7 +36,7 @@ cat << EOF | awk '{ print $1 }' | sort > "$want_submodules"
  80ed4d0bbf65d57cc267dfc63bd2584557f11f9b third_party/googleapis (common-protos-1_3_1-915-g80ed4d0bb)
  c9ccac7cb7345901884aabf5d1a786cfa6e2f397 third_party/googletest (6e2f397)
  15ae750151ac9341e5945eb38f8982d59fb99201 third_party/libuv (v1.34.0)
- fe1790ca0df67173702f70d5646b82f48f412b99 protobuf (v3.7.0-rc.2-756-gfe1790ca0)
+ d0bfd5221182da1a7cc280f3337b5e41a89539cf third_party/protobuf (v3.7.0-rc.2-784-gd0bfd5221)
  c0a080f4bea50bc087cdd8551143ee538cf3459e third_party/protoc-gen-validate (v0.0.10)
  db4b343e48c1264bb4d9ff491b059300701dc7c7 third_party/udpa (heads/master)
  cacf7f1d4e3d44d871b605da3b647f07d718623f third_party/zlib (v1.2.11)