[ios] Removed unused annotation image code

Removed unused annotation image code from iosapp, now that bulk-added point annotations are backed by annotation views.

platform/ios/app/MBXViewController.m

@@ -603,82 +603,6 @@ - (MGLAnnotationView *)mapView:(MGLMapView *)mapView viewForAnnotation:(id<MGLAn
     return annotationView;
 }
 
-- (MGLAnnotationImage *)mapView:(MGLMapView * __nonnull)mapView imageForAnnotation:(id <MGLAnnotation> __nonnull)annotation
-{
-    if ([annotation isKindOfClass:[MBXDroppedPinAnnotation class]]
-        || [annotation isKindOfClass:[MBXCustomCalloutAnnotation class]])
-    {
-        return nil; // use default marker
-    }
-
-    NSString *title = [(MGLPointAnnotation *)annotation title];
-    if (!title.length) return nil;
-    NSString *lastTwoCharacters = [title substringFromIndex:title.length - 2];
-
-    MGLAnnotationImage *annotationImage = [mapView dequeueReusableAnnotationImageWithIdentifier:lastTwoCharacters];
-
-    if ( ! annotationImage)
-    {
-        UIColor *color;
-
-        // make every tenth annotation blue
-        if ([lastTwoCharacters hasSuffix:@"0"]) {
-            color = [UIColor blueColor];
-        } else {
-            color = [UIColor redColor];
-        }
-
-        UIImage *image = [self imageWithText:lastTwoCharacters backgroundColor:color];
-        annotationImage = [MGLAnnotationImage annotationImageWithImage:image reuseIdentifier:lastTwoCharacters];
-
-        // don't allow touches on blue annotations
-        if ([color isEqual:[UIColor blueColor]]) annotationImage.enabled = NO;
-    }
-
-    return annotationImage;
-}
-
-- (UIImage *)imageWithText:(NSString *)text backgroundColor:(UIColor *)color
-{
-    CGRect rect = CGRectMake(0, 0, 20, 15);
-
-    UIGraphicsBeginImageContextWithOptions(rect.size, NO, [[UIScreen mainScreen] scale]);
-
-    CGContextRef ctx = UIGraphicsGetCurrentContext();
-
-    CGContextSetFillColorWithColor(ctx, [[color colorWithAlphaComponent:0.75] CGColor]);
-    CGContextFillRect(ctx, rect);
-
-    CGContextSetStrokeColorWithColor(ctx, [[UIColor blackColor] CGColor]);
-    CGContextStrokeRectWithWidth(ctx, rect, 2);
-
-    NSAttributedString *drawString = [[NSAttributedString alloc] initWithString:text attributes:@{
-        NSFontAttributeName: [UIFont fontWithName:@"Arial-BoldMT" size:12],
-        NSForegroundColorAttributeName: [UIColor whiteColor],
-    }];
-    CGSize stringSize = drawString.size;
-    CGRect stringRect = CGRectMake((rect.size.width - stringSize.width) / 2,
-                                   (rect.size.height - stringSize.height) / 2,
-                                   stringSize.width,
-                                   stringSize.height);
-    [drawString drawInRect:stringRect];
-
-    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
-    UIGraphicsEndImageContext();
-    return image;
-}
-
-- (void)mapView:(MGLMapView *)mapView didDeselectAnnotation:(id<MGLAnnotation>)annotation {
-    NSString *title = [(MGLPointAnnotation *)annotation title];
-    if ( ! title.length)
-    {
-        return;
-    }
-    NSString *lastTwoCharacters = [title substringFromIndex:title.length - 2];
-    MGLAnnotationImage *annotationImage = [mapView dequeueReusableAnnotationImageWithIdentifier:lastTwoCharacters];
-    annotationImage.image = annotationImage.image ? nil : [self imageWithText:lastTwoCharacters backgroundColor:[UIColor grayColor]];
-}
-
 - (BOOL)mapView:(__unused MGLMapView *)mapView annotationCanShowCallout:(__unused id <MGLAnnotation>)annotation
 {
     return YES;