Created web::UserAgentType.

ios/web/navigation/navigation_manager_impl.mm

 // Copyright 2013 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/web/navigation/navigation_manager_impl.h"
 
 #include <stddef.h>
 
 #include <utility>
 
 #include "base/logging.h"
 #import "ios/web/navigation/crw_session_controller+private_constructors.h"
 #import "ios/web/navigation/crw_session_controller.h"
 #import "ios/web/navigation/navigation_item_impl.h"
 #import "ios/web/navigation/navigation_manager_delegate.h"
 #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"
 
 #if !defined(__has_feature) || !__has_feature(objc_arc)
 #error "This file requires ARC support."
 #endif
 
 namespace {
 
 // Checks whether or not two URL are an in-page navigation (differing only
@@ skipping 148 matching lines @@
 void NavigationManagerImpl::AddPendingItem(
     const GURL& url,
     const web::Referrer& referrer,
     ui::PageTransition navigation_type,
     NavigationInitiationType initiation_type) {
   [session_controller_ addPendingItem:url
                              referrer:referrer
                            transition:navigation_type
                        initiationType:initiation_type];
 
-  // Do nothing if pending item is the same as last committed item.
-  if (GetPendingItem()) {
-    bool use_desktop_user_agent =
-        override_desktop_user_agent_for_next_pending_item_ ||
-        (GetLastCommittedItem() &&
-         GetLastCommittedItem()->IsOverridingUserAgent());
-    GetPendingItem()->SetIsOverridingUserAgent(use_desktop_user_agent);
+  // Set the user agent type for web URLs.
+  NavigationItem* pending_item = GetPendingItem();
+  if (pending_item) {
+    // |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_web_item = GetLastCommittedWebItem();
+      DCHECK(!last_web_item ||
+             last_web_item->GetUserAgentType() != UserAgentType::NONE);
+      bool use_desktop_user_agent =
+          override_desktop_user_agent_for_next_pending_item_ ||
+          (last_web_item &&
+           last_web_item->GetUserAgentType() == UserAgentType::DESKTOP);

[Eugene But (OOO till 7-30), 2017/02/25 01:51:52]

How about adding one more local variable for "(last_web_item &&
last_web_item->GetUserAgentType() == UserAgentType::DESKTOP)"?

[kkhorimoto, 2017/02/27 23:29:04]

Done.

+      if (use_desktop_user_agent)
+        pending_item->SetUserAgentType(UserAgentType::DESKTOP);
+    }
     override_desktop_user_agent_for_next_pending_item_ = false;
   }
 }
 
 NavigationItem* NavigationManagerImpl::GetLastUserItem() const {
   return [session_controller_ lastUserItem];
 }
 
 NavigationItem* NavigationManagerImpl::GetPreviousItem() const {
   return [session_controller_ previousItem];
@@ skipping 197 matching lines @@
     // simply add the remainder.
     result += offset;
     if (result < 0 /* overflow */)
       result = INT_MAX;
   }
 
   return result;
 }
 
 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 {
   DCHECK_GT(index, 0);
   DCHECK_LT(index, GetItemCount());
   ui::PageTransition transition = GetItemAtIndex(index)->GetTransitionType();
   return transition & ui::PAGE_TRANSITION_IS_REDIRECT_MASK;
 }
 
+NavigationItem* NavigationManagerImpl::GetLastCommittedWebItem() const {

[Eugene But (OOO till 7-30), 2017/02/25 01:51:52]

From this name I would think that it returns the last http or https Item (see
f.e. UrlHasWebScheme). How about GetLastCommittedNonAppSpecificItem?

[kkhorimoto, 2017/02/27 23:29:04]

Done.

+  int index = GetCurrentItemIndex();
+  NavigationItemList items = [session_controller_ items];
+  if (index < 0 || index >= static_cast<int>(items.size()))

[Eugene But (OOO till 7-30), 2017/02/25 01:51:52]

Can index even be larger than size?

[kkhorimoto, 2017/02/27 23:29:04]

No, it would have DCHECKED when we set it to an invalid value, so I'm leaving it
out of this check.

+    return nullptr;
+  WebClient* client = GetWebClient();
+  while (index >= 0) {

[Eugene But (OOO till 7-30), 2017/02/25 01:51:52]

Do you want to use for-loop here?:

WebClient* client = GetWebClient();
NavigationItemList items = [session_controller_ items];
for (int i = GetCurrentItemIndex(); 0 <= i; i--) {
  if (!client->IsAppSpecificURL(items[index]->GetVirtualURL()))
    return item;
}
return nullptr;

[kkhorimoto, 2017/02/27 23:29:04]

Since we already fetch the current index when performing the check above, I
didn't want to fetch it again to initialize the for loop.  Writing for loops
with an empty initialization section seems hacky to me, so I'm leaving it as a
while loop.

[Eugene But (OOO till 7-30), 2017/03/02 03:36:34]

You actually don't need that check above. You can keep it your way, but this
while loop looks confusing. This code has initialization, condition and
increment, and for loop puts a structure to it.

+    NavigationItem* item = items[index--];
+    if (!client->IsAppSpecificURL(item->GetVirtualURL()))
+      return item;
+  }
+  return nullptr;
+}
+
 }  // namespace web