Add Data Saver support to Cronet

components/cronet/android/cronet_url_request_context_adapter.cc

Index: components/cronet/android/cronet_url_request_context_adapter.cc
diff --git a/components/cronet/android/cronet_url_request_context_adapter.cc b/components/cronet/android/cronet_url_request_context_adapter.cc
index 843d9a97d0e09600dc911358f3795321dbb72b24..a712019841eba16448807bd211214a6f4cc96d53 100644
--- a/components/cronet/android/cronet_url_request_context_adapter.cc
+++ b/components/cronet/android/cronet_url_request_context_adapter.cc
@@ -10,8 +10,10 @@
 #include "base/files/file_util.h"
 #include "base/files/scoped_file.h"
 #include "base/logging.h"
+#include "base/memory/scoped_vector.h"
 #include "base/single_thread_task_runner.h"
 #include "base/values.h"
+#include "components/cronet/android/cronet_data_reduction_proxy.h"
 #include "components/cronet/url_request_context_config.h"
 #include "jni/CronetUrlRequestContext_jni.h"
 #include "net/base/load_flags.h"
@@ -22,6 +24,7 @@
 #include "net/proxy/proxy_service.h"
 #include "net/url_request/url_request_context.h"
 #include "net/url_request/url_request_context_builder.h"
+#include "net/url_request/url_request_interceptor.h"
 
 namespace {
 
@@ -132,8 +135,6 @@ void CronetURLRequestContextAdapter::InitRequestContextOnMainThread(
     jobject jcaller) {
   base::android::ScopedJavaGlobalRef<jobject> jcaller_ref;
   jcaller_ref.Reset(env, jcaller);
-  proxy_config_service_.reset(net::ProxyService::CreateSystemProxyConfigService(
-      GetNetworkTaskRunner(), nullptr));
   GetNetworkTaskRunner()->PostTask(
       FROM_HERE,
       base::Bind(&CronetURLRequestContextAdapter::InitializeOnNetworkThread,
@@ -147,13 +148,35 @@ void CronetURLRequestContextAdapter::InitializeOnNetworkThread(
         jcronet_url_request_context) {
   DCHECK(GetNetworkTaskRunner()->BelongsToCurrentThread());
   DCHECK(!is_context_initialized_);
-  DCHECK(proxy_config_service_);
   // TODO(mmenke):  Add method to have the builder enable SPDY.
   net::URLRequestContextBuilder context_builder;
-  context_builder.set_network_delegate(new BasicNetworkDelegate());
-  context_builder.set_proxy_config_service(proxy_config_service_.release());
+  scoped_ptr<net::NetLog> net_log(new net::NetLog);
+  DCHECK(!data_reduction_proxy_);
+  // For now, the choice to enable the data reduction proxy happens once,
+  // at initialization. It cannot be disabled thereafter.
+  if (config->enable_data_reduction_proxy) {
+    data_reduction_proxy_.reset(
+        new CronetDataReductionProxy(
+            config->data_reduction_proxy_key,
+            config->data_reduction_proxy_options,
+            GetNetworkTaskRunner(),
+            net_log.get()));
+    context_builder.set_network_delegate(
+        data_reduction_proxy_->CreateNetworkDelegate(
+            make_scoped_ptr(new BasicNetworkDelegate())).release());
+    ScopedVector<net::URLRequestInterceptor> interceptors;
+    interceptors.push_back(data_reduction_proxy_->CreateInterceptor());
+    context_builder.SetInterceptors(interceptors.Pass());
+  } else {
+    context_builder.set_network_delegate(new BasicNetworkDelegate());
+  }
+  context_builder.set_proxy_service(
+      net::ProxyService::CreateWithoutProxyResolver(

[mmenke, 2015/04/01 15:46:14]

Why aren't you using CreateUsingSystemProxyResolver, like the builder does?

[bengr, 2015/04/24 02:30:43]

Done.

+          net::ProxyService::CreateSystemProxyConfigService(

[mmenke, 2015/04/01 15:46:14]

It's my understanding that the Java proxy config service needs to be created on
the main thread, to avoid any races.  All calls from the system to this service
are made on the main thread, and we aren't ready to receive them until we're
done creating the service.

[bengr, 2015/04/24 02:30:43]

Done.

+              GetNetworkTaskRunner(), nullptr),
+              net_log.get()));
   config->ConfigureURLRequestContextBuilder(&context_builder);
-
+  context_builder.set_net_log(net_log.release());
   context_.reset(context_builder.Build());
 
   default_load_flags_ = net::LOAD_DO_NOT_SAVE_COOKIES |
@@ -214,6 +237,10 @@ void CronetURLRequestContextAdapter::InitializeOnNetworkThread(
     tasks_waiting_for_context_.front().Run();
     tasks_waiting_for_context_.pop();
   }
+  if (data_reduction_proxy_) {
+    data_reduction_proxy_->Init(config->enable_data_reduction_proxy,
+                                GetURLRequestContext());
+  }
 }
 
 void CronetURLRequestContextAdapter::Destroy(JNIEnv* env, jobject jcaller) {