[DO NOT MERGE] Initiailize APP_SEARCH_IMRPOVEMENT flag outside DEBUG builds.

This is addressing a bug where flags are only changed on debug build
devices or initially when changes. When nexuslauncher restarts the flag
is no longer retrieved.

Change-Id: Ieb6f460a271c918ee4e493b34692244f39cb3740
(cherry picked from commit e1664fcf14)

src/com/android/launcher3/config/BaseFlags.java

@@ -132,6 +132,7 @@ public abstract class BaseFlags {
                 }
             }
         }
+        APP_SEARCH_IMPROVEMENTS.initialize(context);
     }
 
     static List<TogglableFlag> getTogglableFlags() {