fix: remove share button (MESSENGER-8137)

Riot/Modules/MatrixKit/Controllers/MXKPreviewViewController.m

@@ -9,7 +9,10 @@ Please see LICENSE in the repository root for full details.
 #import "MXKPreviewViewController.h"
 @import QuickLook;
 
-@interface MXKPreviewViewController () <QLPreviewControllerDataSource>
+@interface MXKPreviewViewController () <QLPreviewControllerDataSource> {
+    // BWI #8137 remove share button
+    NSTimer *removeShareButtonTimer;
+}
 
 /// A specialized view controller for previewing an item.
 @property (nonatomic, weak) QLPreviewController *previewController;
@@ -63,6 +66,30 @@ Please see LICENSE in the repository root for full details.
     
     if (!self.allowActions)
     {
+        // BWI #8137 remove share button
+        [removeShareButtonTimer invalidate];
+        removeShareButtonTimer = [NSTimer scheduledTimerWithTimeInterval:1.0 repeats:YES block:^(NSTimer * _Nonnull timer) {
+            [self removeShareButtons];
+        }];
+    }
+}
+
+
+- (IBAction)doneAction:(id)sender
+{
+    // BWI #8137 remove share button
+    [removeShareButtonTimer invalidate];
+    removeShareButtonTimer = nil;
+    [self dismissViewControllerAnimated:YES completion:^{
+        if ([self.previewDelegate respondsToSelector:@selector(previewViewControllerDidEndPreview:)]) {
+            [self.previewDelegate previewViewControllerDidEndPreview:self];
+        }
+    }];
+}
+
+// BWI #8137 remove share button
+- (void)removeShareButtons
+{
     NSMutableArray *items = [NSMutableArray arrayWithArray: self.previewController.navigationItem.rightBarButtonItems];
     if (items.count > 0)
     {
@@ -73,17 +100,6 @@ Please see LICENSE in the repository root for full details.
     self.previewController.toolbarItems = nil;
     // bwi: no title to disallow sharing/printing
     self.previewController.navigationItem.title = @"";
-    }
-}
-
-
-- (IBAction)doneAction:(id)sender
-{
-    [self dismissViewControllerAnimated:YES completion:^{
-        if ([self.previewDelegate respondsToSelector:@selector(previewViewControllerDidEndPreview:)]) {
-            [self.previewDelegate previewViewControllerDidEndPreview:self];
-        }
-    }];
 }
 
 #pragma mark - QLPreviewControllerDataSource