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

components/cronet.gypi

Index: components/cronet.gypi
diff --git a/components/cronet.gypi b/components/cronet.gypi
index 054d872335ba797c15e5969251a2101460f68e72..2a85a852de98aff1b6bcdfd3aec424783d654584 100644
--- a/components/cronet.gypi
+++ b/components/cronet.gypi
@@ -11,6 +11,7 @@
           'target_name': 'cronet_jni_headers',
           'type': 'none',
           'sources': [
+            'cronet/android/java/src/org/chromium/net/CronetLibraryLoader.java',
             'cronet/android/java/src/org/chromium/net/CronetUrlRequest.java',
             'cronet/android/java/src/org/chromium/net/CronetUrlRequestContext.java',
             'cronet/android/java/src/org/chromium/net/ChromiumUrlRequest.java',
@@ -231,6 +232,7 @@
               '**/ChromiumUrlRequestFactory.java',
               '**/ChromiumUrlRequestPriority.java',
               '**/CronetResponseInfo.java',
+              '**/CronetLibraryLoader.java',
               '**/CronetUrlRequest.java',
               '**/CronetUrlRequestContext.java',
               '**/CronetUrlRequestFactory.java',