Fix lint issues.

lint.xml

@@ -15,6 +15,7 @@
 
     <issue id="RestrictedApi" severity="error">
         <ignore path="src/org/thoughtcrime/securesms/mediasend/camerax/VideoCapture.java" />
+        <ignore path="src/org/thoughtcrime/securesms/mediasend/camerax/CameraXModule.java" />
     </issue>
 
 </lint>

src/org/thoughtcrime/securesms/mediasend/CameraXFragment.java

@@ -282,7 +282,8 @@ public class CameraXFragment extends Fragment implements CameraFragment {
   }
 
   private boolean isVideoRecordingSupported(@NonNull Context context) {
-    return MediaConstraints.isVideoTranscodeAvailable() &&
+    return Build.VERSION.SDK_INT >= 26                  &&
+           MediaConstraints.isVideoTranscodeAvailable() &&
            CameraXUtil.isMixedModeSupported(context)    &&
            VideoUtil.getMaxVideoDurationInSeconds(context, viewModel.getMediaConstraints()) > 0;
   }