Revert of Simplify BrowserContext by removing redundant methods.

extensions/shell/browser/shell_oauth2_token_service_delegate.cc

Index: extensions/shell/browser/shell_oauth2_token_service_delegate.cc
diff --git a/extensions/shell/browser/shell_oauth2_token_service_delegate.cc b/extensions/shell/browser/shell_oauth2_token_service_delegate.cc
index 759f3e2f24c829ccdc40f6983fb1209d4b7f1d9a..89eb2120447028e417e22256bded7dcdc1020ad4 100644
--- a/extensions/shell/browser/shell_oauth2_token_service_delegate.cc
+++ b/extensions/shell/browser/shell_oauth2_token_service_delegate.cc
@@ -5,8 +5,6 @@
 #include "extensions/shell/browser/shell_oauth2_token_service_delegate.h"
 
 #include <vector>
-
-#include "content/public/browser/storage_partition.h"
 
 namespace extensions {
 
@@ -42,8 +40,7 @@
 
 net::URLRequestContextGetter*
 ShellOAuth2TokenServiceDelegate::GetRequestContext() const {
-  return content::BrowserContext::GetDefaultStoragePartition(browser_context_)->
-      GetURLRequestContext();
+  return browser_context_->GetRequestContext();
 }
 
 std::vector<std::string> ShellOAuth2TokenServiceDelegate::GetAccounts() {