Proper flip asset

// FREEBIE

Signal/Images.xcassets/video-switch-camera-unselected.imageset/Contents.json

@@ -0,0 +1,21 @@
+{
+  "images" : [
+    {
+      "idiom" : "universal",
+      "filename" : "switch_camera_large.png",
+      "scale" : "1x"
+    },
+    {
+      "idiom" : "universal",
+      "scale" : "2x"
+    },
+    {
+      "idiom" : "universal",
+      "scale" : "3x"
+    }
+  ],
+  "info" : {
+    "version" : 1,
+    "author" : "xcode"
+  }
+}

Signal/src/ViewControllers/CallViewController.swift

@@ -379,11 +379,9 @@ class CallViewController: OWSViewController, CallObserver, CallServiceObserver,
         videoModeMuteButton.accessibilityLabel = NSLocalizedString("CALL_VIEW_MUTE_LABEL", comment: "Accessibility label for muting the microphone")
         videoModeMuteButton.alpha = 0.9
 
-        // TODO proper asset
-        videoModeFlipCameraButton = createButton(image: #imageLiteral(resourceName: "btnRefresh--white"),
+        videoModeFlipCameraButton = createButton(image: #imageLiteral(resourceName: "video-switch-camera-unselected"),
                                                  action: #selector(didPressFlipCamera))
-        videoModeFlipCameraButton.setImage(#imageLiteral(resourceName: "btnRefresh--white"),
-                                           for: .selected)
+
         videoModeFlipCameraButton.accessibilityLabel = NSLocalizedString("CALL_VIEW_SWITCH_CAMERA_DIRECTION", comment: "Accessibility label to toggle front vs. rear facing camera")
         videoModeFlipCameraButton.alpha = 0.9