Revert Clang version back to r328903. (#131)

diff --git a/WORKSPACE b/WORKSPACE
index 5dda819..4f70e76 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -96,19 +96,19 @@
 )
 
 # TODO(xingao) Switch to use "marketplace.gcr.io" registry once Buildkite support proper auth.
-# l.gcr.io/google/clang-debian8:r333878
+# l.gcr.io/google/clang-debian8:r328903
 container_pull(
     name = "debian8-clang",
-    digest = "sha256:7d204d8e2dff80c67e65c39096d3ef0671919d1a6170ab535db606aa550e2395",
+    digest = "sha256:8bb65bf0a0da8be48bbac07ebe743805f3dc5259203e19517098162bd23a768f",
     registry = "l.gcr.io",
     repository = "google/clang-debian8",
 )
 
 # TODO(xingao) Switch to use "marketplace.gcr.io" registry once Buildkite support proper auth.
-# l.gcr.io/google/clang-ubuntu:r333878
+# l.gcr.io/google/clang-ubuntu:r328903
 container_pull(
     name = "ubuntu16_04-clang",
-    digest = "sha256:38f658a36015f3091b8f0b808eca586aa45b97e1ec98f03656c1262f9591f63b",
+    digest = "sha256:d553634f23f7c437ca35bbc4b6f1f38bb81be32b9ef2df4329dcd36762277bf7",
     registry = "l.gcr.io",
     repository = "google/clang-ubuntu",
 )
diff --git a/third_party/clang/revision.bzl b/third_party/clang/revision.bzl
index fc918f6..6551eac 100644
--- a/third_party/clang/revision.bzl
+++ b/third_party/clang/revision.bzl
@@ -1,7 +1,7 @@
-CLANG_REVISION = "r335143"
+CLANG_REVISION = "r328903"
 
-DEBIAN8_CLANG_SHA256 = "24d455b33fda3b8439c7b4b93ad893284a44759da7e94f030ae20f60ade6fddc"
+DEBIAN8_CLANG_SHA256 = "8f460b909788ffd8dd467ea4ee106ccd08b4a43408dd98ac8e3938a9b6452bb7"
 
-DEBIAN9_CLANG_SHA256 = "6a56ae0186e3b9bf416078f7ec8a7aafcf7c62eb6883d77002978b7621a0f822"
+DEBIAN9_CLANG_SHA256 = "350f77999033e39a02294406250df819cacb2106daa7b04b5fd6bfe7aa0ab5a1"
 
-UBUNTU16_04_CLANG_SHA256 = "84181025c7808fbf932640aed4c1db8e3ef5eb2d8cbc30c714f3855e04c8fbf0"
+UBUNTU16_04_CLANG_SHA256 = "f1874c57aa1e34c09595a4a0e03b91d7bf89dd7ad044ff4834b46198ff2e9d14"
diff --git a/third_party/libcxx/revision.bzl b/third_party/libcxx/revision.bzl
index c8abac1..9d34c97 100644
--- a/third_party/libcxx/revision.bzl
+++ b/third_party/libcxx/revision.bzl
@@ -1,7 +1,7 @@
-LIBCXX_REVISION = "r335143"
+LIBCXX_REVISION = "r328903"
 
-DEBIAN8_LIBCXX_SHA256 = "441b8f898c579a7958b95c43eaa821e46fbc3340d8e5e513eea8fc8e39155d44"
+DEBIAN8_LIBCXX_SHA256 = "d9798333832690577ca740acb3016a803be684ad0ed02e78922424b4b651f8ce"
 
-DEBIAN9_LIBCXX_SHA256 = "914d17341c5e71796d977b15221ed86c44951a67cc4f98706a5c90c0ee3c035c"
+DEBIAN9_LIBCXX_SHA256 = "66219b838f8d243c071a4c094e13ef78082cd858d87841dd607839a351680b90"
 
-UBUNTU16_04_LIBCXX_SHA256 = "42c884c366c8bd66ee95db59d774efd77fb0273a1c05ecca67837c1ca69d75fe"
+UBUNTU16_04_LIBCXX_SHA256 = "786a35a813e493342a018c04b8fb951a8b34a7d7e377e1ac793db738fc240451"