Update device permissions dialog ui for Chrome apps and extensions

extensions/browser/api/device_permissions_prompt.h

Index: extensions/browser/api/device_permissions_prompt.h
diff --git a/extensions/browser/api/device_permissions_prompt.h b/extensions/browser/api/device_permissions_prompt.h
index cbe5e8ff6e6ba4865ec1f52b667e8255f419e6a3..cbb3b652a7d0ee9ba57d2c79208f2c4a012358bc 100644
--- a/extensions/browser/api/device_permissions_prompt.h
+++ b/extensions/browser/api/device_permissions_prompt.h
@@ -68,7 +68,8 @@ class DevicePermissionsPrompt {
     // implementation should register an observer.
     class Observer {
      public:
-      virtual void OnDevicesChanged() = 0;
+      virtual void OnDeviceAdded(size_t index) = 0;
+      virtual void OnDeviceRemoved(size_t index) = 0;
 
      protected:
       virtual ~Observer();
@@ -81,8 +82,6 @@ class DevicePermissionsPrompt {
     // Only one observer may be registered at a time.
     virtual void SetObserver(Observer* observer);
 
-    virtual base::string16 GetHeading() const = 0;
-    base::string16 GetPromptMessage() const;
     size_t GetDeviceCount() const { return devices_.size(); }
     base::string16 GetDeviceName(size_t index) const;
     base::string16 GetDeviceSerialNumber(size_t index) const;