Use Android callback API to obtain cellular signal strength

net/android/cellular_signal_strength_unittest.cc

Index: net/android/cellular_signal_strength_unittest.cc
diff --git a/net/android/cellular_signal_strength_unittest.cc b/net/android/cellular_signal_strength_unittest.cc
index c6f879723e54870ddfe70ed3d353d568463d1178..86e96976c00131931ccb332cdd5f5f77bf8d8716 100644
--- a/net/android/cellular_signal_strength_unittest.cc
+++ b/net/android/cellular_signal_strength_unittest.cc
@@ -6,6 +6,7 @@
 
 #include <stdint.h>
 
+#include "base/optional.h"
 #include "net/base/network_change_notifier.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ -13,41 +14,21 @@ namespace net {
 
 namespace {
 
-TEST(CellularSignalStrengthAndroidTest, SignalStrengthTest) {
-  int signal_strength_dbm = INT32_MIN;
-  bool signal_strength_available =
-      android::cellular_signal_strength::GetSignalStrengthDbm(
-          &signal_strength_dbm);
-
-  // Signal strength is unavailable if the device does not have an active
-  // cellular connection.
-  if (!NetworkChangeNotifier::IsConnectionCellular(
-          NetworkChangeNotifier::GetConnectionType())) {
-    return;
-  }
-
-  EXPECT_TRUE(signal_strength_available);
-  // Signal strength (in dbM) should typically be between -130 and 0.
-  EXPECT_LE(-130, signal_strength_dbm);
-  EXPECT_GE(0, signal_strength_dbm);
-}
-
 TEST(CellularSignalStrengthAndroidTest, SignalStrengthLevelTest) {
-  int signal_strength_level = INT32_MIN;
-  bool signal_strength_level_available =
-      android::cellular_signal_strength::GetSignalStrengthLevel(
-          &signal_strength_level);
+  base::Optional<int32_t> signal_strength =
+      android::cellular_signal_strength::GetSignalStrengthLevel();
 
   // Signal strength is unavailable if the device does not have an active
   // cellular connection.
   if (!NetworkChangeNotifier::IsConnectionCellular(
           NetworkChangeNotifier::GetConnectionType())) {
+    EXPECT_FALSE(signal_strength);
     return;
   }
 
-  EXPECT_TRUE(signal_strength_level_available);
-  EXPECT_LE(0, signal_strength_level);
-  EXPECT_GE(4, signal_strength_level);
+  EXPECT_TRUE(signal_strength);
+  EXPECT_LE(0, signal_strength.value());
+  EXPECT_GE(4, signal_strength.value());
 }
 
 }  // namespace