Move temp file functions to base namespace.

remoting/host/pairing_registry_delegate_linux_unittest.cc

Index: remoting/host/pairing_registry_delegate_linux_unittest.cc
diff --git a/remoting/host/pairing_registry_delegate_linux_unittest.cc b/remoting/host/pairing_registry_delegate_linux_unittest.cc
index 70cd5583fce3bb355ce77cfd66739095aee57eed..5ca9c94f91aabf79fd4f6e4555ec894109ecef6d 100644
--- a/remoting/host/pairing_registry_delegate_linux_unittest.cc
+++ b/remoting/host/pairing_registry_delegate_linux_unittest.cc
@@ -19,7 +19,7 @@ class PairingRegistryDelegateLinuxTest : public testing::Test {
     // Create a temporary directory in order to get a unique name and use a
     // subdirectory to ensure that PairingRegistryDelegateLinux::Save() creates
     // the parent directory if it doesn't exist.
-    file_util::CreateNewTempDirectory("chromoting-test", &temp_dir_);
+    base::CreateNewTempDirectory("chromoting-test", &temp_dir_);
     temp_registry_ = temp_dir_.Append("paired-clients");
   }