[ios] Added web// public API to let embedder observe loading progress.

ios/web/web_state/web_state_delegate_stub.h

Index: ios/web/web_state/web_state_delegate_stub.h
diff --git a/ios/web/web_state/web_state_delegate_stub.h b/ios/web/web_state/web_state_delegate_stub.h
new file mode 100644
index 0000000000000000000000000000000000000000..afd86acd98d665a4b314f581a333cfd06d177a65
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+++ b/ios/web/web_state/web_state_delegate_stub.h
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+// Copyright 2016 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.
+
+#ifndef IOS_WEB_WEB_STATE_WEB_STATE_DELEGATE_STUB_H_
+#define IOS_WEB_WEB_STATE_WEB_STATE_DELEGATE_STUB_H_
+
+#import "ios/testing/ocmock_complex_type_helper.h"
+#import "ios/web/public/web_state/web_state_delegate_bridge.h"
+
+// Stub implementation for CRWWebStateDelegate protocol.
+@interface CRWWebStateDelegateStub
+    : OCMockComplexTypeHelper<CRWWebStateDelegate>
+// web::WebState received in delegate method calls..
+@property(nonatomic, readonly) web::WebState* webState;
+// Progress received in |webState:didChangeProgress| call.
+@property(nonatomic, readonly) double changedProgress;
+@end
+
+#endif  // IOS_WEB_WEB_STATE_WEB_STATE_DELEGATE_STUB_H_