Fix FileDetailFragment not starting

- opens on specified tab
- opens when launched from PreviewImageActivity

Signed-off-by: ZetaTom <70907959+ZetaTom@users.noreply.github.com>

app/src/main/java/com/owncloud/android/ui/fragment/FileDetailFragment.java

@@ -352,12 +352,13 @@ public class FileDetailFragment extends FileFragment implements OnClickListener,
             }
         });
 
-        // FIXME file detail not opening from Media tab
+        binding.tabLayout.post(() -> {
             if (binding != null) {
                 TabLayout.Tab tab = binding.tabLayout.getTabAt(activeTab);
                 if (tab == null) return;
-            binding.tabLayout.selectTab(tab);
+                tab.select();
             }
+        });
     }
 
     @Override

app/src/main/java/com/owncloud/android/ui/preview/PreviewImageActivity.kt

@@ -357,7 +357,7 @@ class PreviewImageActivity : FileActivity(), FileFragment.ContainerActivity, OnR
         }
 
         startActivity(intent)
-        backToDisplayActivity()
+        finish()
     }
 
     override fun showDetails(file: OCFile, activeTab: Int) {