Store network_service cache in memory

mojo/services/network/network_context.cc

 // Copyright 2014 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.
 
 #include "mojo/services/network/network_context.h"
 
 #include "base/base_paths.h"
 #include "base/path_service.h"
 #include "net/proxy/proxy_service.h"
 #include "net/url_request/url_request_context.h"
 #include "net/url_request/url_request_context_builder.h"
 
 namespace mojo {
 
 NetworkContext::NetworkContext(const base::FilePath& base_path) {
   net::URLRequestContextBuilder builder;
   builder.set_accept_language("en-us,en");
   // TODO(darin): This is surely the wrong UA string.
   builder.set_user_agent("Mojo/0.1");
   builder.set_proxy_service(net::ProxyService::CreateDirect());
   builder.set_transport_security_persister_path(base_path);
 
   net::URLRequestContextBuilder::HttpCacheParams cache_params;
   cache_params.path = base_path.Append(FILE_PATH_LITERAL("Cache"));
-  cache_params.type = net::URLRequestContextBuilder::HttpCacheParams::DISK;
+  // TODO(esprehn): For now store the cache in memory so we can run many shells
+  // in parallel when running tests, otherwise the network services in each
+  // shell will corrupt the disk cache.
+  cache_params.type = net::URLRequestContextBuilder::HttpCacheParams::IN_MEMORY;
   builder.EnableHttpCache(cache_params);
 
   builder.set_file_enabled(true);
 
   url_request_context_.reset(builder.Build());
 }
 
 NetworkContext::~NetworkContext() {
   // TODO(darin): Be careful about destruction order of member variables?
 }
 
 }  // namespace mojo