network_diagnostics: Return kProblem for unknown signal strength

This change ensures that a problem isn't returned for a routine that
isn't run.

BUG=chromium:956783
TEST=unit_tests --gtest_filter=SignalStrengthRoutineTest.*

Change-Id: I226b632aa65aeb1a9873ce4ac6ae0380f6c3b5c0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2364033Reviewed-by: Steven Bennetts <stevenjb@chromium.org>
Commit-Queue: Kartik Hegde <khegde@chromium.org>
Cr-Commit-Position: refs/heads/master@{#799797}

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

@@ -60,7 +60,7 @@ void SignalStrengthRoutine::RunRoutine(SignalStrengthRoutineCallback callback) {
 
 void SignalStrengthRoutine::AnalyzeResultsAndExecuteCallback() {
   if (signal_strength_ == kUnknownSignalStrength) {
-    set_verdict(mojom::RoutineVerdict::kNotRun);
+    set_verdict(mojom::RoutineVerdict::kProblem);
     problems_.emplace_back(mojom::SignalStrengthProblem::kSignalNotFound);
   } else if (signal_strength_ < kSignalStrengthThreshold) {
     set_verdict(mojom::RoutineVerdict::kProblem);

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

@@ -106,7 +106,7 @@ TEST_F(SignalStrengthRoutineTest, TestUnknownSignal) {
       mojom::SignalStrengthProblem::kSignalNotFound};
   signal_strength_routine()->RunRoutine(
       base::BindOnce(&SignalStrengthRoutineTest::CompareVerdict, weak_ptr(),
-                     mojom::RoutineVerdict::kNotRun, expected_problems));
+                     mojom::RoutineVerdict::kProblem, expected_problems));
   base::RunLoop().RunUntilIdle();
 }