Add methods for controlling keyboard brightness.

chromeos/dbus/power_manager_client.h

Index: chromeos/dbus/power_manager_client.h
diff --git a/chromeos/dbus/power_manager_client.h b/chromeos/dbus/power_manager_client.h
index 3526890d092cc948136ae0c551119aa0869c7ee2..63551f23c3a1feb417ace82180e32cb119b0b3ae 100644
--- a/chromeos/dbus/power_manager_client.h
+++ b/chromeos/dbus/power_manager_client.h
@@ -119,6 +119,12 @@ class CHROMEOS_EXPORT PowerManagerClient {
   virtual void GetScreenBrightnessPercent(
       const GetScreenBrightnessPercentCallback& callback) = 0;
 
+  // Decreases the keyboard brightness.
+  virtual void DecreaseKeyboardBrightness() = 0;
+
+  // Increases the keyboard brightness.
+  virtual void IncreaseKeyboardBrightness() = 0;
+
   // Request for power supply status update.
   virtual void RequestStatusUpdate(UpdateRequestType update_type) = 0;