chromeos: Use stl utilities from the base namespace

chromeos/audio/audio_devices_pref_handler_stub.cc

Index: chromeos/audio/audio_devices_pref_handler_stub.cc
diff --git a/chromeos/audio/audio_devices_pref_handler_stub.cc b/chromeos/audio/audio_devices_pref_handler_stub.cc
index 82a5b4a5d3278e5d12600552743fdb226887e92e..9f71356a457d909406df7993d940ba354e9f461e 100644
--- a/chromeos/audio/audio_devices_pref_handler_stub.cc
+++ b/chromeos/audio/audio_devices_pref_handler_stub.cc
@@ -18,8 +18,10 @@ AudioDevicesPrefHandlerStub::~AudioDevicesPrefHandlerStub() {
 double AudioDevicesPrefHandlerStub::GetOutputVolumeValue(
     const AudioDevice* device) {
   if (!device ||
-      !ContainsKey(audio_device_volume_gain_map_, device->stable_device_id))
+      !base::ContainsKey(audio_device_volume_gain_map_,
+                         device->stable_device_id)) {
     return kDefaultOutputVolumePercent;
+  }
   return audio_device_volume_gain_map_[device->stable_device_id];
 }
 
@@ -27,8 +29,10 @@ double AudioDevicesPrefHandlerStub::GetInputGainValue(
     const AudioDevice* device) {
   // TODO(rkc): The default value for gain is wrong. http://crbug.com/442489
   if (!device ||
-      !ContainsKey(audio_device_volume_gain_map_, device->stable_device_id))
+      !base::ContainsKey(audio_device_volume_gain_map_,
+                         device->stable_device_id)) {
     return 75.0;
+  }
   return audio_device_volume_gain_map_[device->stable_device_id];
 }