Export all CWV* symbols from the ios/web_view dynamic library.

ios/web_view/public/cwv_navigation_delegate.h

 // 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.
 
 #ifndef IOS_WEB_VIEW_PUBLIC_CWV_NAVIGATION_DELEGATE_H_
 #define IOS_WEB_VIEW_PUBLIC_CWV_NAVIGATION_DELEGATE_H_
 
 #import <Foundation/Foundation.h>
 
+#include "cwv_export.h"
+
 @protocol CRIWVTranslateDelegate;
 @class CWVWebView;
 
 // Navigation delegate protocol for CWVWebViews.  Allows embedders to hook
 // page loading and receive events for navigation.
-@protocol CWVNavigationDelegate<NSObject>
+CWV_EXPORT @protocol CWVNavigationDelegate<NSObject>
 @optional
 
 // Asks delegate if WebView should start the load. WebView will
 // load the request if this method is not implemented.
 - (BOOL)webView:(CWVWebView*)webView
     shouldStartLoadWithRequest:(NSURLRequest*)request;
 
 // Asks delegate if WebView should continue the load. WebView
 // will load the response if this method is not implemented.
 - (BOOL)webView:(CWVWebView*)webView
@@ skipping 10 matching lines @@
 // both success and failure cases.
 - (void)webView:(CWVWebView*)webView didLoadPageWithSuccess:(BOOL)success;
 
 // Notifies the delegate that web view process was terminated
 // (usually by crashing, though possibly by other means).
 - (void)webViewWebContentProcessDidTerminate:(CWVWebView*)webView;
 
 @end
 
 #endif  // IOS_WEB_VIEW_PUBLIC_CWV_NAVIGATION_DELEGATE_H_