shill: Replace NULL with nullptr.

BUG=None
TEST=`USE=wimax FEATURES=test emerge-$BOARD shill`

Change-Id: I30ab47ff32dcadad09ae7a2baf4d4123a6ef0d8e
Reviewed-on: https://chromium-review.googlesource.com/220657
Reviewed-by: Ben Chan <benchan@chromium.org>
Tested-by: Ben Chan <benchan@chromium.org>
Commit-Queue: Ben Chan <benchan@chromium.org>
diff --git a/static_ip_parameters_unittest.cc b/static_ip_parameters_unittest.cc
index d23dcd5..e492514 100644
--- a/static_ip_parameters_unittest.cc
+++ b/static_ip_parameters_unittest.cc
@@ -196,7 +196,7 @@
 
   {
     Error error;
-    EXPECT_FALSE(store.GetStringProperty("StaticIP.Address", NULL, &error));
+    EXPECT_FALSE(store.GetStringProperty("StaticIP.Address", nullptr, &error));
     EXPECT_EQ(Error::kNotFound, error.type());
   }
   string string_value;
@@ -205,7 +205,7 @@
   EXPECT_EQ(kGateway, string_value);
   {
     Error error;
-    EXPECT_FALSE(store.GetInt32Property("StaticIP.Mtu", NULL, &error));
+    EXPECT_FALSE(store.GetInt32Property("StaticIP.Mtu", nullptr, &error));
     EXPECT_EQ(Error::kNotFound, error.type());
   }
   EXPECT_TRUE(store.GetStringProperty("StaticIP.NameServers", &string_value,