Camera2: getSceneMode should return NULL when there are no supported scene modes

Bug: 8444806
Change-Id: Ic92924ceda3de738a7971605552baf00a4fc0546
diff --git a/services/camera/libcameraservice/camera2/Parameters.cpp b/services/camera/libcameraservice/camera2/Parameters.cpp
index 859e2e9..d13fe8b 100644
--- a/services/camera/libcameraservice/camera2/Parameters.cpp
+++ b/services/camera/libcameraservice/camera2/Parameters.cpp
@@ -534,6 +534,8 @@
         if (!noSceneModes) {
             params.set(CameraParameters::KEY_SUPPORTED_SCENE_MODES,
                     supportedSceneModes);
+        } else {
+            params.remove(CameraParameters::KEY_SCENE_MODE);
         }
     }