Hide the status bar in the image picker / attachment approval.

Signal/src/ViewControllers/ConversationView/ConversationViewController.m

@@ -2836,7 +2836,9 @@ typedef enum : NSUInteger {
             OWSImagePickerGridController *picker = [OWSImagePickerGridController new];
             picker.delegate = self;
 
-            pickerModal = [[OWSNavigationController alloc] initWithRootViewController:picker];
+            OWSNavigationController *modal = [[OWSNavigationController alloc] initWithRootViewController:picker];
+            modal.ows_prefersStatusBarHidden = @(YES);
+            pickerModal = modal;
         } else {
             UIImagePickerController *picker = [OWSImagePickerController new];
             picker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;

SignalMessaging/ViewControllers/AttachmentApprovalViewController.swift

@@ -169,6 +169,7 @@ public class AttachmentApprovalViewController: UIPageViewController, UIPageViewC
         let vc = AttachmentApprovalViewController(mode: .modal, attachments: attachments)
         vc.approvalDelegate = approvalDelegate
         let navController = OWSNavigationController(rootViewController: vc)
+        navController.ows_prefersStatusBarHidden = true
 
         guard let navigationBar = navController.navigationBar as? OWSNavigationBar else {
             owsFailDebug("navigationBar was nil or unexpected class")
@@ -198,6 +199,10 @@ public class AttachmentApprovalViewController: UIPageViewController, UIPageViewC
 
     // MARK: - View Lifecycle
 
+    public override var prefersStatusBarHidden: Bool {
+        return true
+    }
+
     override public func viewDidLoad() {
         super.viewDidLoad()
 
@@ -229,8 +234,6 @@ public class AttachmentApprovalViewController: UIPageViewController, UIPageViewC
         Logger.debug("")
         super.viewWillAppear(animated)
 
-        CurrentAppContext().setStatusBarHidden(true, animated: animated)
-
         guard let navigationBar = navigationController?.navigationBar as? OWSNavigationBar else {
             owsFailDebug("navigationBar was nil or unexpected class")
             return
@@ -251,10 +254,6 @@ public class AttachmentApprovalViewController: UIPageViewController, UIPageViewC
     override public func viewWillDisappear(_ animated: Bool) {
         Logger.debug("")
         super.viewWillDisappear(animated)
-
-        // Since this VC is being dismissed, the "show status bar" animation would feel like
-        // it's occuring on the presenting view controller - it's better not to animate at all.
-        CurrentAppContext().setStatusBarHidden(false, animated: false)
     }
 
     override public var inputAccessoryView: UIView? {

SignalMessaging/ViewControllers/OWSNavigationController.h

@@ -1,5 +1,5 @@
 //
-//  Copyright (c) 2018 Open Whisper Systems. All rights reserved.
+//  Copyright (c) 2019 Open Whisper Systems. All rights reserved.
 //
 
 #import <UIKit/UIKit.h>
@@ -23,6 +23,11 @@ NS_ASSUME_NONNULL_BEGIN
 // unsaved changes.
 @interface OWSNavigationController : UINavigationController
 
+// If set, this property lets us override prefersStatusBarHidden behavior.
+// This is useful for supressing the status bar while a modal is presented,
+// regardless of which view is currently visible.
+@property (nonatomic, nullable) NSNumber *ows_prefersStatusBarHidden;
+
 @end
 
 NS_ASSUME_NONNULL_END

SignalMessaging/ViewControllers/OWSNavigationController.m

@@ -69,6 +69,14 @@ NS_ASSUME_NONNULL_BEGIN
     self.interactivePopGestureRecognizer.delegate = self;
 }
 
+- (BOOL)prefersStatusBarHidden
+{
+    if (self.ows_prefersStatusBarHidden) {
+        return self.ows_prefersStatusBarHidden.boolValue;
+    }
+    return [super prefersStatusBarHidden];
+}
+
 #pragma mark - UINavigationBarDelegate
 
 - (void)setupNavbar