[ios] Use chrome_browser_state_forward.h in /ios/public/provider

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.

Bug: 1042208
Change-Id: I027bdc72608c52aed8414ce1926fe5b4edd7c074
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2011820
Auto-Submit: Sylvain Defresne <sdefresne@chromium.org>
Commit-Queue: Rohit Rao <rohitrao@chromium.org>
Reviewed-by: Rohit Rao <rohitrao@chromium.org>
Cr-Commit-Position: refs/heads/master@{#733599}

ios/public/provider/chrome/browser/BUILD.gn

@@ -20,6 +20,7 @@ source_set("browser") {
     "//base",
     "//components/metrics",
     "//ios//web/public",
+    "//ios/chrome/browser/browser_state:forward",
     "//ios/public/provider/chrome/browser/mailto",
   ]
   libs = [ "CoreLocation.framework" ]

ios/public/provider/chrome/browser/chrome_browser_provider.h

@@ -15,6 +15,7 @@
 
 #include "base/memory/ref_counted.h"
 #include "base/observer_list.h"
+#include "ios/chrome/browser/browser_state/chrome_browser_state_forward.h"
 
 class AppDistributionProvider;
 class BrandedImageProvider;
@@ -45,7 +46,6 @@ class Browser;
 namespace ios {
 
 class ChromeBrowserProvider;
-class ChromeBrowserState;
 class ChromeIdentityService;
 class GeolocationUpdaterProvider;
 class SigninErrorProvider;

ios/public/provider/chrome/browser/mailto/BUILD.gn

@@ -8,7 +8,10 @@ source_set("mailto") {
     "mailto_handler_provider.h",
     "mailto_handler_provider.mm",
   ]
-  deps = [ "//base" ]
+  deps = [
+    "//base",
+    "//ios/chrome/browser/browser_state:forward",
+  ]
 }
 
 source_set("test_support") {

ios/public/provider/chrome/browser/mailto/mailto_handler_provider.h

@@ -6,11 +6,9 @@
 #define IOS_PUBLIC_PROVIDER_CHROME_BROWSER_MAILTO_MAILTO_HANDLER_PROVIDER_H_
 
 #import <UIKit/UIKit.h>
-#include "base/macros.h"
 
-namespace ios {
-class ChromeBrowserState;
-}  // namespace ios
+#include "base/macros.h"
+#include "ios/chrome/browser/browser_state/chrome_browser_state_forward.h"
 
 @class ChromeIdentity;
 

ios/public/provider/chrome/browser/voice/BUILD.gn

@@ -16,7 +16,10 @@ source_set("voice") {
     "voice_search_provider.h",
     "voice_search_provider.mm",
   ]
-  deps = [ "//base" ]
+  deps = [
+    "//base",
+    "//ios/chrome/browser/browser_state:forward",
+  ]
 }
 
 source_set("test_support") {

ios/public/provider/chrome/browser/voice/voice_search_provider.h

@@ -10,15 +10,12 @@
 
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
+#include "ios/chrome/browser/browser_state/chrome_browser_state_forward.h"
 
 @protocol ApplicationCommands;
 class AudioSessionController;
 class VoiceSearchController;
 
-namespace ios {
-class ChromeBrowserState;
-}
-
 // VoiceSearchProvider allows embedders to provide functionality related to
 // voice search.
 class VoiceSearchProvider {