[iOS][MF] Fix insets for iOS 13

Bug: 1004749
Change-Id: I3c6560e27d38e9880d7bdd2b09235db38ecc336a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1809164
Commit-Queue: Javier Ernesto Flores Robles <javierrobles@chromium.org>
Reviewed-by: Olivier Robin <olivierrobin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#697205}

ios/chrome/browser/ui/autofill/manual_fill/fallback_view_controller.h

@@ -23,6 +23,7 @@
 
 // If set to YES, the controller will add negative content insets inverse to the
 // ones added by UITableViewController to accommodate for the keyboard.
+// Not needed and ignored on iOS >= 13.
 @property(nonatomic, assign) BOOL contentInsetsAlwaysEqualToSafeArea;
 
 // Data source for images.

ios/chrome/browser/ui/autofill/manual_fill/fallback_view_controller.mm

@@ -141,6 +141,15 @@ constexpr CGFloat kMinimumLoadingTime = 0.5;
   [self presentQueuedActionItems];
 }
 
+#pragma mark - Getters
+
+- (BOOL)contentInsetsAlwaysEqualToSafeArea {
+  if (@available(iOS 13, *)) {
+    return NO;
+  }
+  return _contentInsetsAlwaysEqualToSafeArea;
+}
+
 #pragma mark - Private
 
 // Presents the data items currently in queue.