[ios] Deprecated -[MGLMapView emptyMemoryCache]

Deprecated -[MGLMapView emptyMemoryCache]. Switched ios-bench to a redeclared -didReceiveMemoryWarning as a workaround.

Fixes #1833.

platform/ios/CHANGELOG.md

@@ -12,6 +12,7 @@ Mapbox welcomes participation and contributions from everyone.  If you’d like
 - Added a `-reloadStyle:` action to MGLMapView to force a reload of the current style. ([#4728](https://github.com/mapbox/mapbox-gl-native/pull/4728))
 - A more specific user agent string is now sent with style and tile requests. ([#4012](https://github.com/mapbox/mapbox-gl-native/pull/4012))
 - Removed unused SVG files from the SDK’s resource bundle. ([#4641](https://github.com/mapbox/mapbox-gl-native/pull/4641))
+- Deprecated `-[MGLMapView emptyMemoryCache]`. ([#4725](https://github.com/mapbox/mapbox-gl-native/pull/4725))
 
 ## 3.2.0
 

platform/ios/app/MBXViewController.m

@@ -159,7 +159,6 @@ static const CLLocationCoordinate2D WorldTourDestinations[] = {
                             ((debugMask & MGLMapDebugCollisionBoxesMask)
                              ? @"Hide Collision Boxes"
                              : @"Show Collision Boxes"),
-                            @"Empty Memory",
                             @"Add 100 Points",
                             @"Add 1,000 Points",
                             @"Add 10,000 Points",
@@ -201,21 +200,17 @@ static const CLLocationCoordinate2D WorldTourDestinations[] = {
     }
     else if (buttonIndex == actionSheet.firstOtherButtonIndex + 5)
     {
-        [self.mapView emptyMemoryCache];
+        [self parseFeaturesAddingCount:100];
     }
     else if (buttonIndex == actionSheet.firstOtherButtonIndex + 6)
     {
-        [self parseFeaturesAddingCount:100];
+        [self parseFeaturesAddingCount:1000];
     }
     else if (buttonIndex == actionSheet.firstOtherButtonIndex + 7)
-    {
-        [self parseFeaturesAddingCount:1000];
-    }
-    else if (buttonIndex == actionSheet.firstOtherButtonIndex + 8)
     {
         [self parseFeaturesAddingCount:10000];
     }
-    else if (buttonIndex == actionSheet.firstOtherButtonIndex + 9)
+    else if (buttonIndex == actionSheet.firstOtherButtonIndex + 8)
     {
         // PNW triangle
         //
@@ -282,19 +277,19 @@ static const CLLocationCoordinate2D WorldTourDestinations[] = {
             free(polygonCoordinates);
         }
     }
-    else if (buttonIndex == actionSheet.firstOtherButtonIndex + 10)
+    else if (buttonIndex == actionSheet.firstOtherButtonIndex + 9)
     {
         [self startWorldTour:actionSheet];
     }
-    else if (buttonIndex == actionSheet.firstOtherButtonIndex + 11)
+    else if (buttonIndex == actionSheet.firstOtherButtonIndex + 10)
     {
         [self presentAnnotationWithCustomCallout];
     }
-    else if (buttonIndex == actionSheet.firstOtherButtonIndex + 12)
+    else if (buttonIndex == actionSheet.firstOtherButtonIndex + 11)
     {
         [self.mapView removeAnnotations:self.mapView.annotations];
     }
-    else if (buttonIndex == actionSheet.firstOtherButtonIndex + 13)
+    else if (buttonIndex == actionSheet.firstOtherButtonIndex + 12)
     {
         if (_isShowingCustomStyleLayer)
         {
@@ -305,12 +300,12 @@ static const CLLocationCoordinate2D WorldTourDestinations[] = {
             [self insertCustomStyleLayer];
         }
     }
-    else if (buttonIndex == actionSheet.firstOtherButtonIndex + 14)
+    else if (buttonIndex == actionSheet.firstOtherButtonIndex + 13)
     {
         NSString *fileContents = [NSString stringWithContentsOfFile:[self telemetryDebugLogfilePath] encoding:NSUTF8StringEncoding error:nil];
         NSLog(@"%@", fileContents);
     }
-    else if (buttonIndex == actionSheet.firstOtherButtonIndex + 15)
+    else if (buttonIndex == actionSheet.firstOtherButtonIndex + 14)
     {
         NSString *filePath = [self telemetryDebugLogfilePath];
         if ([[NSFileManager defaultManager] isDeletableFileAtPath:filePath]) {

platform/ios/benchmark/MBXBenchViewController.mm

@@ -16,6 +16,9 @@
 /** Returns whether the map view is currently loading or processing any assets required to render the map */
 - (BOOL)isFullyLoaded;
 
+/** Empties the in-memory tile cache. */
+- (void)didReceiveMemoryWarning;
+
 @end
 
 @interface MBXBenchViewController () <MGLMapViewDelegate>
@@ -142,7 +145,7 @@ static const int benchmarkDuration = 200; // frames
         {
             // Start the benchmarking timer.
             state = State::WarmingUp;
-            [self.mapView emptyMemoryCache];
+            [self.mapView didReceiveMemoryWarning];
             NSLog(@"- Warming up for %d frames...", warmupDuration);
             [mapView setNeedsGLDisplay];
         }

platform/ios/include/MGLMapView.h

@@ -989,10 +989,7 @@ IB_DESIGNABLE
 
 - (void)toggleDebug __attribute__((deprecated("Use -setDebugMask:.")));
 
-/**
-    Empties the in-memory tile cache.
- */
-- (void)emptyMemoryCache;
+- (void)emptyMemoryCache __attribute__((deprecated));
 
 /**
     Resets the map to the minimum zoom level, a center coordinate of (0, 0), and