Helium: Adding vector clock

blimp/net/BUILD.gn

Index: blimp/net/BUILD.gn
diff --git a/blimp/net/BUILD.gn b/blimp/net/BUILD.gn
index 9c3488256c37fc6b164cb2d4c95c9f9d7da0e891..2c6ab3a9c1b578ab5044a567081409cde84f3b24 100644
--- a/blimp/net/BUILD.gn
+++ b/blimp/net/BUILD.gn
@@ -77,6 +77,7 @@ component("net") {
   defines = [ "BLIMP_NET_IMPLEMENTATION=1" ]
 
   deps = [
+    ":helium",
     "//base",
     "//blimp/common",
     "//net",
@@ -90,6 +91,21 @@ component("net") {
   ]
 }
 
+source_set("helium") {
+  sources = [
+    "helium/vector_clock.cc",
+    "helium/vector_clock.h",
+  ]
+  deps = [
+    "//base",
+    "//blimp/common",
+  ]
+
+  public_deps = [
+    "//blimp/common/proto",
+  ]
+}
+
 source_set("test_support") {
   testonly = true
 
@@ -134,6 +150,7 @@ source_set("unit_tests") {
     "compressed_packet_unittest.cc",
     "engine_authentication_handler_unittest.cc",
     "engine_connection_manager_unittest.cc",
+    "helium/vector_clock_unittest.cc",
     "input_message_unittest.cc",
     "ssl_client_transport_unittest.cc",
     "stream_packet_reader_unittest.cc",
@@ -143,6 +160,7 @@ source_set("unit_tests") {
   ]
 
   deps = [
+    ":helium",
     ":net",
     ":test_support",
     "//base",