Make recents visible on resume unless requested otherwise.

If the last interaction left recents invisible, we need to make the
visible again on their next resume.

Bug: 25754031
Change-Id: I4b1d4bae5609bf3f4a77250d3544084afd594536

packages/SystemUI/src/com/android/systemui/recents/RecentsActivity.java

@@ -421,6 +421,8 @@ public class RecentsActivity extends Activity implements RecentsView.RecentsView
         if (state.startHidden) {
             state.startHidden = false;
             mRecentsView.setStackViewVisibility(View.INVISIBLE);
+        } else {
+            mRecentsView.setStackViewVisibility(View.VISIBLE);
         }
     }