(Set)IsOverridingUserAgent should be called on VisibleItem

ios/web/web_state/ui/crw_web_controller.mm

Index: ios/web/web_state/ui/crw_web_controller.mm
diff --git a/ios/web/web_state/ui/crw_web_controller.mm b/ios/web/web_state/ui/crw_web_controller.mm
index bfcc3f987101de631b9de34ac04db4e97a7df7ee..47a576ceeee7b59b82084a502dcb54a9e826abbd 100644
--- a/ios/web/web_state/ui/crw_web_controller.mm
+++ b/ios/web/web_state/ui/crw_web_controller.mm
@@ -458,9 +458,6 @@ @interface CRWWebController ()<CRWContextMenuDelegate,
 
 // Returns YES if the user interacted with the page recently.
 @property(nonatomic, readonly) BOOL userClickedRecently;
-// Returns whether the desktop user agent should be used when setting the user
-// agent.
-@property(nonatomic, readonly) BOOL useDesktopUserAgent;
 
 // Facade for Mojo API.
 @property(nonatomic, readonly) web::MojoFacade* mojoFacade;
@@ -2339,11 +2336,6 @@ - (BOOL)shouldClosePageOnNativeApplicationLoad {
   return rendererInitiatedWithoutInteraction || noNavigationItems;
 }
 
-- (BOOL)useDesktopUserAgent {
-  web::NavigationItem* item = [self currentNavItem];
-  return item && item->IsOverridingUserAgent();
-}
-
 - (web::MojoFacade*)mojoFacade {
   if (!_mojoFacade) {
     service_manager::mojom::InterfaceProvider* interfaceProvider =
@@ -4210,11 +4202,17 @@ - (void)ensureWebViewCreatedWithConfiguration:(WKWebViewConfiguration*)config {
 }
 
 - (WKWebView*)webViewWithConfiguration:(WKWebViewConfiguration*)config {
+  web::NavigationItem* visibleItem =

[Eugene But (OOO till 7-30), 2017/02/23 00:54:24]

Is there a reason for removing |useDesktopUserAgent| method? The old code looked
cleaner.

[liaoyuke, 2017/02/23 01:10:14]

Done.

[kkhorimoto, 2017/02/23 01:16:25]

I suggested removing the old property because of the same reason we wanted to
remove NavigationManager::IsUsingDesktopuserAgent(); it's less error prone to
look inspect a specified item from the NavigationManager than abstracting away
to another function.  Since this is the only place it's used in this class, it
seemed a better solution to include the logic here.  If we do want to
reintroduce the property though, we should use the same naming scheme that we
ultimately used in Tab, as |useDesktopUserAgent| is poorly named.

+      self.navigationManagerImpl ? self.navigationManagerImpl->GetVisibleItem()
+                                 : nil;
+  BOOL isUsingDesktopUseragent =

[Eugene But (OOO till 7-30), 2017/02/23 00:54:24]

shouldUseDesktopUserAgent

Agent capitalized, |is| prefix is good for method names, not for variable names
in Objective-C.

[liaoyuke, 2017/02/23 01:10:14]

Acknowledged.

+      visibleItem && visibleItem->IsOverridingUserAgent();
+
   // Do not attach the context menu controller immediately as the JavaScript
   // delegate must be specified.
   return web::BuildWKWebView(CGRectZero, config,
                              self.webStateImpl->GetBrowserState(),
-                             [self useDesktopUserAgent]);
+                             isUsingDesktopUseragent);
 }
 
 - (void)setWebView:(WKWebView*)webView {