diff --git a/base/third_party/cityhash_v103/src/city_v103.cc b/base/third_party/cityhash_v103/src/city_v103.cc
index 8248068209cf..1f99751c1a60 100644
--- a/base/third_party/cityhash_v103/src/city_v103.cc
+++ b/base/third_party/cityhash_v103/src/city_v103.cc
@@ -32,6 +32,13 @@
 #include <algorithm>
 #include <string.h>  // for memcpy and memset
 
+#include "base/compiler_specific.h"
+#include "build/build_config.h"
+
+namespace base {
+namespace internal {
+namespace cityhash_v103 {
+
 using namespace std;
 
 static uint64 UNALIGNED_LOAD64(const char *p) {
@@ -46,7 +53,7 @@ static uint32 UNALIGNED_LOAD32(const char *p) {
   return result;
 }
 
-#if !defined(WORDS_BIGENDIAN)
+#if defined(ARCH_CPU_LITTLE_ENDIAN)
 
 #define uint32_in_expected_order(x) (x)
 #define uint64_in_expected_order(x) (x)
@@ -71,7 +78,7 @@ static uint32 UNALIGNED_LOAD32(const char *p) {
 #define uint32_in_expected_order(x) (bswap_32(x))
 #define uint64_in_expected_order(x) (bswap_64(x))
 
-#endif  // WORDS_BIGENDIAN
+#endif  // defined(ARCH_CPU_LITTLE_ENDIAN)
 
 #if !defined(LIKELY)
 #if HAVE_BUILTIN_EXPECT
@@ -350,3 +357,7 @@ uint128 CityHash128(const char *s, size_t len) {
     return CityHash128WithSeed(s, len, uint128(k0, k1));
   }
 }
+
+}  // namespace cityhash_v103
+}  // namespace internal
+}  // namespace base
diff --git a/base/third_party/cityhash_v103/src/city_v103.h b/base/third_party/cityhash_v103/src/city_v103.h
index 7a827fbea4ff..3828a78feb54 100644
--- a/base/third_party/cityhash_v103/src/city_v103.h
+++ b/base/third_party/cityhash_v103/src/city_v103.h
@@ -47,6 +47,10 @@
 #include <stdint.h>
 #include <utility>
 
+namespace base {
+namespace internal {
+namespace cityhash_v103 {
+
 typedef uint8_t uint8;
 typedef uint32_t uint32;
 typedef uint64_t uint64;
@@ -87,4 +91,8 @@ inline uint64 Hash128to64(const uint128& x) {
   return b;
 }
 
+}  // namespace cityhash_v103
+}  // namespace internal
+}  // namespace base
+
 #endif  // BASE_THIRD_PARTY_CITYHASH_V103_SRC_CITY_V103_H_