Added NavigationManager::GetIndexOfItem().

ios/web/navigation/crw_session_controller.mm

 // Copyright 2012 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/crw_session_controller.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <utility>
@@ skipping 581 matching lines @@
     _previousItemIndex--;
 
   if (_navigationManager)
     _navigationManager->OnNavigationItemsPruned(1U);
 }
 
 - (BOOL)isSameDocumentNavigationBetweenItem:(web::NavigationItem*)firstItem
                                     andItem:(web::NavigationItem*)secondItem {
   if (!firstItem || !secondItem || firstItem == secondItem)
     return NO;
-  NSUInteger firstIndex = [self indexOfItem:firstItem];
-  NSUInteger secondIndex = [self indexOfItem:secondItem];
-  if (firstIndex == NSNotFound || secondIndex == NSNotFound)
+  int firstIndex = [self indexOfItem:firstItem];
+  int secondIndex = [self indexOfItem:secondItem];
+  if (firstIndex == -1 || secondIndex == -1)
     return NO;
-  NSUInteger startIndex = firstIndex < secondIndex ? firstIndex : secondIndex;
-  NSUInteger endIndex = firstIndex < secondIndex ? secondIndex : firstIndex;
+  int startIndex = firstIndex < secondIndex ? firstIndex : secondIndex;
+  int endIndex = firstIndex < secondIndex ? secondIndex : firstIndex;
 
-  for (NSUInteger i = startIndex + 1; i <= endIndex; i++) {
+  for (int i = startIndex + 1; i <= endIndex; i++) {
     web::NavigationItemImpl* item = self.items[i].get();
     // Every item in the sequence has to be created from a hash change or
     // pushState() call.
     if (!item->IsCreatedFromPushState() && !item->IsCreatedFromHashChange())
       return NO;
     // Every item in the sequence has to have a URL that could have been
     // created from a pushState() call.
     if (!web::history_state_util::IsHistoryStateChangeValid(firstItem->GetURL(),
                                                             item->GetURL()))
       return NO;
   }
   return YES;
 }
 
-- (NSInteger)indexOfItem:(const web::NavigationItem*)item {
+- (int)indexOfItem:(const web::NavigationItem*)item {
   DCHECK(item);
   for (size_t index = 0; index < self.items.size(); ++index) {
     if (self.items[index].get() == item)
       return index;
   }
-  return NSNotFound;
+  return -1;
 }
 
 - (web::NavigationItemImpl*)itemAtIndex:(NSInteger)index {
   if (index < 0 || self.items.size() <= static_cast<NSUInteger>(index))
     return nullptr;
   return self.items[index].get();
 }
 
 #pragma mark -
 #pragma mark Private methods
@@ skipping 43 matching lines @@
   return item;
 }
 
 - (BOOL)isRedirectTransitionForItemAtIndex:(size_t)index {
   DCHECK_LT(index, self.items.size());
   ui::PageTransition transition = self.items[index]->GetTransitionType();
   return (transition & ui::PAGE_TRANSITION_IS_REDIRECT_MASK) ? YES : NO;
 }
 
 @end