[ios] Refactor SessionServiceIOS to remove dependency on BrowserState.

ios/chrome/browser/test/perf_test_with_bvc_ios.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.
 
 #include "ios/chrome/browser/test/perf_test_with_bvc_ios.h"
 
 #import <UIKit/UIKit.h>
 
 #include "base/files/file_path.h"
 #include "base/memory/ptr_util.h"
@@ skipping 98 matching lines @@
   bookmarks::test::WaitForBookmarkModelToLoad(
       ios::BookmarkModelFactory::GetForBrowserState(
           chrome_browser_state_.get()));
   ASSERT_TRUE(chrome_browser_state_->CreateHistoryService(false));
 
   // Force creation of AutocompleteClassifier instance.
   ios::AutocompleteClassifierFactory::GetForBrowserState(
       chrome_browser_state_.get());
 
   // Use the session to create a window which will contain the tab models.
-  SessionWindowIOS* sessionWindow = [[SessionServiceIOS sharedService]
-      loadWindowForBrowserState:chrome_browser_state_.get()];
+  SessionServiceIOS* session_service = [SessionServiceIOS sharedService];
+  NSString* state_path = base::SysUTF8ToNSString(
+      chrome_browser_state_->GetStatePath().AsUTF8Unsafe());
+  NSString* session_path = [session_service sessionPathForDirectory:state_path];
+  SessionWindowIOS* sessionWindow =
+      [session_service loadSessionWindowFromPath:session_path];
 
   // Tab models. The off-the-record (OTR) tab model is required for the stack
   // view controller, which is created in OpenStackView().
   tab_model_.reset([[TabModel alloc]
       initWithSessionWindow:sessionWindow
              sessionService:[SessionServiceIOS sharedService]
                browserState:chrome_browser_state_.get()]);
   otr_tab_model_.reset([[TabModel alloc]
       initWithSessionWindow:sessionWindow
              sessionService:[SessionServiceIOS sharedService]
@@ skipping 35 matching lines @@
   // NSAutoreleasePool can drain. This needs to be done before
   // |chrome_browser_state_| can be cleared. For tests that allocate more
   // objects, more runloop time may be required.
   if (slow_teardown_)
     SpinRunLoop(.5);
   PerfTest::TearDown();
 
   // The profiles can be deallocated only after the BVC has been deallocated.
   chrome_browser_state_.reset();
 }