Fix broken clockstate.network2 histogram and add unit test

components/network_time/network_time_tracker.cc

Index: components/network_time/network_time_tracker.cc
diff --git a/components/network_time/network_time_tracker.cc b/components/network_time/network_time_tracker.cc
index d33de06568655a2f6a136e9a4ba7125385a8f8db..19e02b937ab40cb6e55689667de26e7e3e8b2c5c 100644
--- a/components/network_time/network_time_tracker.cc
+++ b/components/network_time/network_time_tracker.cc
@@ -305,6 +305,10 @@ base::TimeDelta NetworkTimeTracker::GetTimerDelayForTesting() const {
   return timer_.GetCurrentDelay();
 }
 
+void NetworkTimeTracker::EnableTimeQueriesForTesting() {
+  enable_time_queries_for_testing_ = true;

[meacer, 2016/10/17 23:45:48]

If you want to keep the bool as is, I feel like
force_enable_time_queries_for_testing_ is slightly more descriptive. The current
name implies that time queries is always disabled in testing.

+}
+
 NetworkTimeTracker::NetworkTimeResult NetworkTimeTracker::GetNetworkTime(
     base::Time* network_time,
     base::TimeDelta* uncertainty) const {
@@ -500,7 +504,8 @@ void NetworkTimeTracker::QueueCheckTime(base::TimeDelta delay) {
 
 bool NetworkTimeTracker::ShouldIssueTimeQuery() {
   // Do not query the time service if not enabled via Variations Service.
-  if (!base::FeatureList::IsEnabled(kNetworkTimeServiceQuerying)) {
+  if (!base::FeatureList::IsEnabled(kNetworkTimeServiceQuerying) &&
+      !enable_time_queries_for_testing_) {

[meacer, 2016/10/17 21:35:20]

Instead of adding a bool, can the test force enable the feature using
base::FieldTrialList::CreateFieldTrial? Or is that only for field trials and not
features?

[estark, 2016/10/17 21:45:37]

It's possible, but it's takes an annoying large amount of code that I didn't
want to copy-paste:
https://cs.chromium.org/chromium/src/components/network_time/network_time_tra...

WDYT? Better to use that code?

[meacer, 2016/10/17 23:45:48]

Unless you want to refactor that code, I think this is fine.

Otherwise, it would probably make sense to put that code into
network_time_tracker_test_utils.h/cc and then call it from both sides. Hmm, now
that I think about it, maybe we should do this so that we can avoid adding
another bool here? (larger CL, but makes it marginally clearer to read this
class)

[estark, 2016/10/18 03:58:37]

I like that idea, done.

     return false;
   }