Remove obviously unneeded forward declarations from headers under src/{app,base,net}.

net/proxy/proxy_config_service_common_unittest.h

 // Copyright (c) 2010 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 NET_PROXY_PROXY_CONFIG_SERVICE_COMMON_UNITTEST_H_
 #define NET_PROXY_PROXY_CONFIG_SERVICE_COMMON_UNITTEST_H_
 #pragma once
 
 #include "net/proxy/proxy_config.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 // Helper functions to describe the expected value of a
 // ProxyConfig::ProxyRules, and to check for a match.
 
 namespace net {
 
-class ProxyBypassRules;
-
 // This structure contains our expectations on what values the ProxyRules
 // should have.
 struct ProxyRulesExpectation {
   ProxyRulesExpectation(ProxyConfig::ProxyRules::Type type,
                         const char* single_proxy,
                         const char* proxy_for_http,
                         const char* proxy_for_https,
                         const char* proxy_for_ftp,
                         const char* socks_proxy,
                         const char* flattened_bypass_rules,
@@ skipping 55 matching lines @@
   const char* proxy_for_https;
   const char* proxy_for_ftp;
   const char* socks_proxy;
   const char* flattened_bypass_rules;
   bool reverse_bypass;
 };
 
 }  // namespace net
 
 #endif  // NET_PROXY_PROXY_CONFIG_SERVICE_COMMON_UNITTEST_H_