ui: update theme, add night mode support

Change-Id: Id7de59c49e45b0e914dae257b8f539537170300a
diff --git a/ring-android/app/src/main/res/layout/camerapicker.xml b/ring-android/app/src/main/res/layout/camerapicker.xml
index 006a8e7..3333559 100644
--- a/ring-android/app/src/main/res/layout/camerapicker.xml
+++ b/ring-android/app/src/main/res/layout/camerapicker.xml
@@ -19,6 +19,6 @@
         android:padding="16dp"
         app:backgroundTint="@color/holo_green_dark"
         app:rippleColor="@android:color/white"
-        app:srcCompat="@drawable/ic_photo_camera"
+        app:srcCompat="@drawable/baseline_photo_camera_24"
         app:useCompatPadding="true" />
 </RelativeLayout>
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