Revert of Make ProfileIOData use URLRequestContextBuilder

chrome/browser/io_thread.h

Index: chrome/browser/io_thread.h
diff --git a/chrome/browser/io_thread.h b/chrome/browser/io_thread.h
index 9cc54ee4984ac1a120ee26a67e896d6402c13519..593491bf83a014aa4a967dc58369466a0e7c8ae7 100644
--- a/chrome/browser/io_thread.h
+++ b/chrome/browser/io_thread.h
@@ -89,7 +89,6 @@
 class RTTAndThroughputEstimatesObserver;
 class SSLConfigService;
 class URLRequestContext;
-class URLRequestContextBuilderMojo;
 class URLRequestContextGetter;
 
 namespace ct {
@@ -233,13 +232,6 @@
   bool WpadQuickCheckEnabled() const;
   bool PacHttpsUrlStrippingEnabled() const;
 
-  // Configures |builder|'s ProxyService to use the specified
-  // |proxy_config_service| and sets a number of proxy-related options based on
-  // prefs, policies, and the command line.
-  void SetUpProxyConfigService(
-      net::URLRequestContextBuilderMojo* builder,
-      std::unique_ptr<net::ProxyConfigService> proxy_config_service) const;
-
  private:
   friend class test::IOThreadPeer;
   friend class chrome::TestingIOThreadState;