[Cronet] Hook up library loader, system proxy and network change notifier to async api.

components/cronet/android/cronet_url_request_context.cc

Index: components/cronet/android/cronet_url_request_context.cc
diff --git a/components/cronet/android/cronet_url_request_context.cc b/components/cronet/android/cronet_url_request_context.cc
index a9b6014217c7ffd110f42fa9a90a4eea5a3227da..c3de3945bc51e850d8f58bb0cae27433b890182f 100644
--- a/components/cronet/android/cronet_url_request_context.cc
+++ b/components/cronet/android/cronet_url_request_context.cc
@@ -49,15 +49,8 @@ static jlong CreateRequestContextAdapter(JNIEnv* env,
   base::android::ScopedJavaLocalRef<jobject> scoped_context(env, japp_context);

[xunjieli, 2015/01/05 18:22:45]

base::android::InitApplicationContext is already done in
"CronetInitOnMainThread".

[mef, 2015/01/05 19:32:41]

Done.

   base::android::InitApplicationContext(env, scoped_context);
 
-  base::android::ScopedJavaGlobalRef<jobject> jcaller_ref;
-  jcaller_ref.Reset(env, jcaller);
-
   CronetURLRequestContextAdapter* context_adapter =
       new CronetURLRequestContextAdapter();
-  base::Closure init_java_network_thread = base::Bind(&initJavaNetworkThread,
-                                                      jcaller_ref);
-  context_adapter->Initialize(context_config.Pass(), init_java_network_thread);
-
   return reinterpret_cast<jlong>(context_adapter);
 }
 
@@ -106,4 +99,31 @@ static jint SetMinLogLevel(JNIEnv* env, jobject jcaller, jint jlog_level) {
   return old_log_level;
 }
 
+// Called on application's main Java thread.
+static void InitRequestContextOnMainThread(JNIEnv* env,
+                                           jobject jcaller,
+                                           jlong jurl_request_context_adapter,
+                                           jstring jconfig) {
+  if (jurl_request_context_adapter == 0)
+    return;
+
+  std::string config_string =
+      base::android::ConvertJavaStringToUTF8(env, jconfig);
+  scoped_ptr<URLRequestContextConfig> context_config(
+      new URLRequestContextConfig());
+  if (!context_config->LoadFromJSON(config_string))

[xunjieli, 2015/01/05 18:22:45]

Hmm.. we probably should avoid doing things on the main UI thread. Converting
config string and loading from JSON should probably still remain on the network
thread. Since it is already done in CreateRequestContextAdapter, could you get
it from a member variable instead?

[mef, 2015/01/05 19:32:41]

The config used to be a member of CronetURLRequestContextAdapter, but  IIRC it
was removed by Matt's suggestion. 

I'm fine with bringing it back in (it would also be useful for default load
flags) if there are no objections. Matt, WDYT?

+    return;
+
+  CronetURLRequestContextAdapter* context_adapter =
+      reinterpret_cast<CronetURLRequestContextAdapter*>(
+          jurl_request_context_adapter);
+
+  base::android::ScopedJavaGlobalRef<jobject> jcaller_ref;
+  jcaller_ref.Reset(env, jcaller);
+  base::Closure init_java_network_thread = base::Bind(&initJavaNetworkThread,
+                                                      jcaller_ref);
+  context_adapter->InitRequestContextOnMainThread(
+      context_config.Pass(), init_java_network_thread);
+}
+
 }  // namespace cronet