[Android WebView] Get rid of secondary HttpNetworkSession

net/url_request/url_request_context_builder.h

Index: net/url_request/url_request_context_builder.h
diff --git a/net/url_request/url_request_context_builder.h b/net/url_request/url_request_context_builder.h
index 135e7483fd95555c2c2099f7613e0042066b710e..260eccb7147b652783ff78adc24d0680eac8dff4 100644
--- a/net/url_request/url_request_context_builder.h
+++ b/net/url_request/url_request_context_builder.h
@@ -52,8 +52,12 @@ class NET_EXPORT URLRequestContextBuilder {
  public:
   struct NET_EXPORT HttpCacheParams {
     enum Type {
+      // In-memory cache.
       IN_MEMORY,
+      // Disk cache using "default" backend.
       DISK,
+      // Disk cache using "simple" backend (SimpleBackendImpl).
+      DISK_SIMPLE,
     };
 
     HttpCacheParams();