Creates alertCoordinatorDelegate for alerts

ios/chrome/browser/ui/alert_coordinator/action_sheet.mm

Index: ios/chrome/browser/ui/alert_coordinator/action_sheet.mm
diff --git a/ios/chrome/browser/ui/alert_coordinator/action_sheet.mm b/ios/chrome/browser/ui/alert_coordinator/action_sheet.mm
new file mode 100644
index 0000000000000000000000000000000000000000..01471fe65d206fbd1e5613d8f472085219fd6254
--- /dev/null
+++ b/ios/chrome/browser/ui/alert_coordinator/action_sheet.mm
@@ -0,0 +1,54 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#import "ios/chrome/browser/ui/alert_coordinator/action_sheet.h"
+
+#import "ios/web/public/web_state/context_menu_params.h"
+
+@interface ActionSheet () {
+  // Parameters that define what is shown in the context menu.

[lpromero, 2016/07/18 12:11:35]

This comment should rather be in the header.

Moreover, it defines what *and how it* is shown, right?

And maybe s/context menu/action sheet?

+  web::ContextMenuParams _params;
+}
+
+@end
+
+@implementation ActionSheet
+
+- (instancetype)initWithParams:(const web::ContextMenuParams&)params {
+  self = [super init];
+  if (self) {
+    _params = params;
+  }
+  return self;
+}
+
+#pragma mark - Private Methods

[lpromero, 2016/07/18 12:11:35]

These are AlertCoordinatorDelegate methods, not private methods.

+
+- (BOOL)alertCoordinatorShouldStart:(AlertCoordinator*)alertCoordinator {
+  // Check that the view is still visible on screen, otherwise just return and
+  // don't show the context menu.

[lpromero, 2016/07/18 12:11:35]

Idem s/context menu/action sheet.

+  return [_params.view window] || [_params.view isKindOfClass:[UIWindow class]];
+}
+
+- (UIAlertController*)alertCoordinatorUIAlertController:
+    (AlertCoordinator*)alertCoordinator {
+  DCHECK([_params.view
+      isDescendantOfView:[alertCoordinator.baseViewController view]]);
+  UIAlertController* alert = [UIAlertController

[marq (ping after 24h), 2016/07/18 13:02:41]

I don't like the idea of a coordinator being handed the view controller it's
going to manage. I'd prefer that the coordinator delegate protocol allow it to
collect the title, style, and source view/rect but have the coordinator itself
handle creating the view controller.

Consider: Suppose we have a "drop-in" MDC action sheet replacement we want to
try out. If the coordinator creates and owns the view controller it defines,
then that change can be encapsulated inside the view controller. With this API,
we have to update the delegate protocol and anything that implements it.

+      alertControllerWithTitle:_params.menu_title
+                       message:alertCoordinator.message
+                preferredStyle:UIAlertControllerStyleActionSheet];
+  alert.popoverPresentationController.sourceView = _params.view;
+  alert.popoverPresentationController.sourceRect =
+      CGRectMake(_params.location.x, _params.location.y, 1.0, 1.0);

[lpromero, 2016/07/18 12:11:35]

Is the location passed in params already localized for RTL?

[gambard, 2016/07/18 12:40:20]

I am looking into it.

+
+  return alert;
+}
+
+- (BOOL)alertCoordinatorShouldAddCancelButton:
+    (AlertCoordinator*)alertCoordinator {
+  return YES;
+}
+
+@end