Simplify BrowserContext by removing redundant methods.

android_webview/native/aw_contents_statics.cc

Index: android_webview/native/aw_contents_statics.cc
diff --git a/android_webview/native/aw_contents_statics.cc b/android_webview/native/aw_contents_statics.cc
index bca0a998fa1fb12d4028c867378cffddf7764498..e3c49efbd140029a756f5d9c3255aef2856d5038 100644
--- a/android_webview/native/aw_contents_statics.cc
+++ b/android_webview/native/aw_contents_statics.cc
@@ -12,6 +12,7 @@
 #include "base/android/scoped_java_ref.h"
 #include "base/callback.h"
 #include "content/public/browser/browser_thread.h"
+#include "content/public/browser/storage_partition.h"
 #include "content/public/common/url_constants.h"
 #include "jni/AwContentsStatics_jni.h"
 #include "net/cert/cert_database.h"
@@ -58,13 +59,14 @@ void SetDataReductionProxyKey(JNIEnv* env,
                               const JavaParamRef<jstring>& key) {
   AwBrowserContext* browser_context = AwBrowserContext::GetDefault();
   DCHECK(browser_context);
-  DCHECK(browser_context->GetRequestContext());
   // The following call to GetRequestContext() could possibly be the first such
   // call, which means AwURLRequestContextGetter::InitializeURLRequestContext
   // will be called on IO thread as a result.
   AwURLRequestContextGetter* aw_url_request_context_getter =
       static_cast<AwURLRequestContextGetter*>(
-          browser_context->GetRequestContext());
+          content::BrowserContext::GetDefaultStoragePartition(browser_context)->
+              GetURLRequestContext());
+  DCHECK(aw_url_request_context_getter);
 
   // This PostTask has to be called after GetRequestContext, because SetKeyOnIO
   // needs a valid DataReductionProxyRequestOptions object.