network_diagnostics: Contain util functions in a namespace

To call utility functions more clearly, wrap them in a "util" namespace.

TEST=unit_tests --gtest_filter=NetworkDiagnosticsUtilTest*
BUG=chromium:956783

Change-Id: I2874dbdbda7fe84c04f7484c876845d75f99f928
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2438757Reviewed-by: Steven Bennetts <stevenjb@chromium.org>
Commit-Queue: Kartik Hegde <khegde@chromium.org>
Cr-Commit-Position: refs/heads/master@{#812481}

chrome/browser/chromeos/net/network_diagnostics/network_diagnostics_util.cc

@@ -16,6 +16,8 @@
 namespace chromeos {
 namespace network_diagnostics {
 
+namespace util {
+
 namespace {
 
 // Returns |num_prefixes| prefixes of size |length|, where no two entries are
@@ -80,5 +82,7 @@ Profile* GetUserProfile() {
   return ProfileManager::GetPrimaryUserProfile();
 }
 
+}  // namespace util
+
 }  // namespace network_diagnostics
 }  // namespace chromeos

chrome/browser/chromeos/net/network_diagnostics/network_diagnostics_util.h

@@ -13,6 +13,8 @@ class Profile;
 namespace chromeos {
 namespace network_diagnostics {
 
+namespace util {
+
 // Returns the Gstatic host suffix. Network diagnostic routines attach a random
 // prefix to |kGstaticHostSuffix| to get a complete hostname.
 const char* GetGstaticHostSuffix();
@@ -36,6 +38,8 @@ std::vector<std::string> GetRandomHostsWithFixedHosts(int num_random_hosts,
 // Returns the profile associated with this account.
 Profile* GetUserProfile();
 
+}  // namespace util
+
 }  // namespace network_diagnostics
 }  // namespace chromeos
 

chrome/browser/chromeos/net/network_diagnostics/network_diagnostics_util_unittest.cc

@@ -14,7 +14,7 @@ namespace network_diagnostics {
 
 TEST(NetworkDiagnosticsUtilTest, TestGetRandomString) {
   int length = 8;
-  auto random_string = GetRandomString(length);
+  auto random_string = util::GetRandomString(length);
   // Ensure that the length equals |length| and all characters are in between
   // 'a'-'z', inclusive.
   ASSERT_EQ(length, random_string.size());
@@ -27,7 +27,7 @@ TEST(NetworkDiagnosticsUtilTest, TestGetRandomHosts) {
   int num_hosts = 10;
   int prefix_length = 8;
   std::vector<std::string> random_hosts =
-      GetRandomHosts(num_hosts, prefix_length);
+      util::GetRandomHosts(num_hosts, prefix_length);
   // Ensure |random_hosts| has unique entries.
   std::sort(random_hosts.begin(), random_hosts.end());
   ASSERT_TRUE(std::adjacent_find(random_hosts.begin(), random_hosts.end()) ==