[ios] Removed redundant storage observer.

iphone/Maps/Classes/CustomViews/MapViewControls/Search/MWMSearchManager.mm

@@ -37,12 +37,11 @@ extern NSString * const kSearchStateKey = @"SearchStateKey";
 @property (nonatomic) MWMSearchTableViewController * tableViewController;
 @property (nonatomic) MWMSearchDownloadViewController * downloadController;
 
+@property (nonatomic) BOOL haveDownloadedMaps;
+
 @end
 
 @implementation MWMSearchManager
-{
-  int m_mapsObserverSlotId;
-}
 
 - (nullable instancetype)initWithParentView:(nonnull UIView *)view
                                    delegate:(nonnull id<MWMSearchManagerProtocol, MWMSearchViewProtocol, MWMRoutingProtocol>)delegate
@@ -55,7 +54,6 @@ extern NSString * const kSearchStateKey = @"SearchStateKey";
     self.rootView.delegate = delegate;
     self.parentView = view;
     self.state = MWMSearchManagerStateHidden;
-    [MWMFrameworkListener addObserver:self];
   }
   return self;
 }
@@ -267,6 +265,11 @@ extern NSString * const kSearchStateKey = @"SearchStateKey";
 
 - (void)changeToDefaultState
 {
+  using namespace storage;
+  auto const & s = GetFramework().Storage();
+  TCountriesVec downloadedCountries, availCountries;
+  s.GetChildrenInGroups(s.GetRootId(), downloadedCountries, availCountries);
+  self.haveDownloadedMaps = !downloadedCountries.empty();
   self.view.alpha = 1.;
   [self updateTopController];
   [self.navigationController popToRootViewControllerAnimated:NO];
@@ -314,19 +317,25 @@ extern NSString * const kSearchStateKey = @"SearchStateKey";
 
 - (UIViewController *)topController
 {
-  using namespace storage;
-  auto & s = GetFramework().Storage();
-  TCountriesVec downloadedCountries, availCountries;
-  s.GetChildrenInGroups(s.GetRootId(), downloadedCountries, availCountries);
-  BOOL const haveMap = (downloadedCountries.size() != 0);
-  return haveMap ? self.tabbedController : self.downloadController;
+  if (self.haveDownloadedMaps || self.state == MWMSearchManagerStateHidden)
+  {
+    return self.tabbedController;
+  }
+  else
+  {
+    if (!self.downloadController)
+      self.downloadController = [[MWMSearchDownloadViewController alloc] initWithDelegate:self];
+    return self.downloadController;
+  }
 }
 
-- (MWMSearchDownloadViewController *)downloadController
+- (void)setDownloadController:(MWMSearchDownloadViewController *)downloadController
 {
-  if (!_downloadController)
-    _downloadController = [[MWMSearchDownloadViewController alloc] initWithDelegate:self];
-  return _downloadController;
+  _downloadController = downloadController;
+  if (downloadController)
+    [MWMFrameworkListener addObserver:self];
+  else
+    [MWMFrameworkListener removeObserver:self];
 }
 
 - (MWMSearchTabbedViewController *)tabbedController

iphone/Maps/Classes/Framework/MWMFrameworkListener.h

@@ -4,6 +4,7 @@
 
 + (MWMFrameworkListener *)listener;
 + (void)addObserver:(id<MWMFrameworkObserver>)observer;
++ (void)removeObserver:(id<MWMFrameworkObserver>)observer;
 
 @property (nonatomic, readonly) location::EMyPositionMode myPositionMode;
 @property (nonatomic) UserMark const * userMark;

iphone/Maps/Classes/Framework/MWMFrameworkListener.mm

@@ -81,6 +81,19 @@ void loopWrappers(TObservers * observers, TLoopBlock block)
   });
 }
 
++ (void)removeObserver:(TObserver)observer
+{
+  dispatch_async(dispatch_get_main_queue(), ^
+  {
+    MWMFrameworkListener * listener = [MWMFrameworkListener listener];
+    [listener.routeBuildingObservers removeObject:observer];
+    [listener.myPositionObservers removeObject:observer];
+    [listener.userMarkObservers removeObject:observer];
+    [listener.storageObservers removeObject:observer];
+    [listener.drapeObservers removeObject:observer];
+  });
+}
+
 - (instancetype)initListener
 {
   self = [super init];