[ios] Use chrome_browser_state_forward.h in /ios/chrome/browser/ui/payments

Instead of forward declaring ChromeBrowserState in the ios
namespace, use a header. This will allow moving the class
to the global namespace without having to change all the
forward declaration at the same time.

This CL was uploaded by git cl split.

R=mahmadi@chromium.org

Bug: 1042208
Change-Id: Ia971578b2b012398b81c4a14d206732411f384b9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2007581Reviewed-by: Moe Ahmadi <mahmadi@chromium.org>
Commit-Queue: Sylvain Defresne <sdefresne@chromium.org>
Auto-Submit: Sylvain Defresne <sdefresne@chromium.org>
Cr-Commit-Position: refs/heads/master@{#733916}

ios/chrome/browser/ui/payments/payment_request_coordinator.h

@@ -10,6 +10,7 @@
 #include "base/ios/block_types.h"
 #include "base/strings/string16.h"
 #include "components/autofill/core/browser/payments/full_card_request.h"
+#include "ios/chrome/browser/browser_state/chrome_browser_state_forward.h"
 #import "ios/chrome/browser/ui/coordinators/chrome_coordinator.h"
 #import "ios/chrome/browser/ui/payments/address_edit_coordinator.h"
 #import "ios/chrome/browser/ui/payments/contact_info_edit_coordinator.h"
@@ -25,10 +26,6 @@ namespace autofill {
 class AutofillManager;
 }  // namespace autofill
 
-namespace ios {
-class ChromeBrowserState;
-}  // namespace ios
-
 namespace payments {
 class PaymentDetails;
 class PaymentRequest;

ios/chrome/browser/ui/payments/payment_request_manager.h

@@ -7,6 +7,8 @@
 
 #import <UIKit/UIKit.h>
 
+#include "ios/chrome/browser/browser_state/chrome_browser_state_forward.h"
+
 // Names identifying the errors used in Payment Request API:
 // https://www.w3.org/TR/payment-request/
 // A complete list of DOMException error names and descriptions can be found at:
@@ -19,10 +21,6 @@ extern NSString* const kNotSupportedError;
 @protocol ApplicationCommands;
 class LocationBarModel;
 
-namespace ios {
-class ChromeBrowserState;
-}  // namespace ios
-
 namespace web {
 class WebState;
 }  // namespace web