Initialize CRIWVWebView with Configuration object instead of browserState.

ios/web_view/internal/criwv_web_view_configuration.mm

+// Copyright 2017 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_view/public/criwv_web_view_configuration.h"
+
+#import "ios/web_view/public/criwv_website_data_store.h"
+
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
+@interface CRIWVWebViewConfiguration ()
+// Initialize configuration with specified data store.
+- (instancetype)initWithDataStore:(CRIWVWebsiteDataStore*)dataStore;
+@end
+
+@implementation CRIWVWebViewConfiguration
+
+@synthesize websiteDataStore = _websiteDataStore;
+
+- (instancetype)init {
+  return [self initWithDataStore:[CRIWVWebsiteDataStore defaultDataStore]];
+}
+
+- (instancetype)initWithDataStore:(CRIWVWebsiteDataStore*)dataStore {
+  self = [super init];
+  if (self) {
+    _websiteDataStore = dataStore;
+  }
+  return self;
+}
+
+// NSCopying
+
+- (id)copyWithZone:(NSZone*)zone {
+  return
+      [[[self class] allocWithZone:zone] initWithDataStore:_websiteDataStore];
+}
+
+@end