Add updater state for Mac.

components/update_client/updater_state_unittest.cc

Index: components/update_client/updater_state_unittest.cc
diff --git a/components/update_client/updater_state_unittest.cc b/components/update_client/updater_state_unittest.cc
index e36c2c65f7074c4d05ecd89a6309bb3f118d18e8..ca889ade7e14f43b54b4bb60e679b8c7d2dad728 100644
--- a/components/update_client/updater_state_unittest.cc
+++ b/components/update_client/updater_state_unittest.cc
@@ -42,9 +42,13 @@ TEST_F(UpdaterStateTest, Serialize) {
   EXPECT_STREQ("1", attributes.at("autoupdatecheckenabled").c_str());
   EXPECT_STREQ("1", attributes.at("updatepolicy").c_str());
 
-#if defined(GOOGLE_CHROME_BUILD) && defined(OS_WIN)
-  // The name of the Windows updater for Chrome.
-  EXPECT_STREQ("Omaha", UpdaterState::GetState(false)->at("name").c_str());
+#if defined(GOOGLE_CHROME_BUILD)
+  #if defined(OS_WIN)
+    // The name of the Windows updater for Chrome.
+    EXPECT_STREQ("Omaha", UpdaterState::GetState(false)->at("name").c_str());
+  #elif defined(OS_MACOSX)
+    EXPECT_STREQ("Keystone", UpdaterState::GetState(false)->at("name").c_str());
+  #endif
 #endif  // GOOGLE_CHROME_BUILD
 
   // Tests some of the remaining values.