Created web::UserAgentType.

ios/web/navigation/navigation_manager_impl.mm

Index: ios/web/navigation/navigation_manager_impl.mm
diff --git a/ios/web/navigation/navigation_manager_impl.mm b/ios/web/navigation/navigation_manager_impl.mm
index bb16cba464bb1a3689eeca3a77fd606ca20e5cfe..71bc8cf56262d87a21cc214e86bf8c28bed4a58f 100644
--- a/ios/web/navigation/navigation_manager_impl.mm
+++ b/ios/web/navigation/navigation_manager_impl.mm
@@ -16,6 +16,7 @@
 #include "ios/web/navigation/navigation_manager_facade_delegate.h"
 #include "ios/web/public/load_committed_details.h"
 #import "ios/web/public/navigation_item.h"
+#import "ios/web/public/web_client.h"
 #import "ios/web/public/web_state/web_state.h"
 #include "ui/base/page_transition_types.h"
 
@@ -184,15 +185,31 @@ bool AreURLsInPageNavigation(const GURL& existing_url, const GURL& new_url) {
                            transition:navigation_type
                        initiationType:initiation_type];
 
-  // Do nothing if pending item is the same as last committed item.
-  if (GetPendingItem()) {
+  // Set the user agent type for web URLs.
+  NavigationItem* pending_item = GetPendingItem();
+  if (!pending_item)
+    return;
+
+  // |override_desktop_user_agent_for_next_pending_item_| must be false if
+  // |pending_item|'s UserAgentType is NONE, as requesting a desktop user
+  // agent should be disabled for app-specific URLs.
+  DCHECK(pending_item->GetUserAgentType() != UserAgentType::NONE ||
+         !override_desktop_user_agent_for_next_pending_item_);
+
+  if (pending_item->GetUserAgentType() != UserAgentType::NONE) {
+    NavigationItem* last_non_native_item = GetLastCommittedNonAppSpecificItem();
+    DCHECK(!last_non_native_item ||
+           last_non_native_item->GetUserAgentType() != UserAgentType::NONE);
+    bool last_web_item_uses_desktop_user_agent =
+        last_non_native_item &&
+        last_non_native_item->GetUserAgentType() == UserAgentType::DESKTOP;
     bool use_desktop_user_agent =
         override_desktop_user_agent_for_next_pending_item_ ||
-        (GetLastCommittedItem() &&
-         GetLastCommittedItem()->IsOverridingUserAgent());
-    GetPendingItem()->SetIsOverridingUserAgent(use_desktop_user_agent);
-    override_desktop_user_agent_for_next_pending_item_ = false;
+        last_web_item_uses_desktop_user_agent;
+    if (use_desktop_user_agent)
+      pending_item->SetUserAgentType(UserAgentType::DESKTOP);
   }
+  override_desktop_user_agent_for_next_pending_item_ = false;
 }
 
 NavigationItem* NavigationManagerImpl::GetLastUserItem() const {
@@ -408,10 +425,15 @@ bool AreURLsInPageNavigation(const GURL& existing_url, const GURL& new_url) {
 }
 
 void NavigationManagerImpl::OverrideDesktopUserAgentForNextPendingItem() {
-  if (GetPendingItem())
-    GetPendingItem()->SetIsOverridingUserAgent(true);
-  else
+  NavigationItem* pending_item = GetPendingItem();
+  if (pending_item) {
+    // The desktop user agent cannot be used for a pending navigation to an
+    // app-specific URL.
+    DCHECK_NE(pending_item->GetUserAgentType(), UserAgentType::NONE);
+    pending_item->SetUserAgentType(UserAgentType::DESKTOP);
+  } else {
     override_desktop_user_agent_for_next_pending_item_ = true;
+  }
 }
 
 bool NavigationManagerImpl::IsRedirectItemAtIndex(int index) const {
@@ -421,4 +443,19 @@ bool AreURLsInPageNavigation(const GURL& existing_url, const GURL& new_url) {
   return transition & ui::PAGE_TRANSITION_IS_REDIRECT_MASK;
 }
 
+NavigationItem* NavigationManagerImpl::GetLastCommittedNonAppSpecificItem()
+    const {
+  int index = GetCurrentItemIndex();
+  if (index == -1)
+    return nullptr;
+  WebClient* client = GetWebClient();
+  NavigationItemList items = [session_controller_ items];
+  while (index >= 0) {
+    NavigationItem* item = items[index--];
+    if (!client->IsAppSpecificURL(item->GetVirtualURL()))
+      return item;
+  }
+  return nullptr;
+}
+
 }  // namespace web