Add TransportContext class.

remoting/client/plugin/pepper_port_allocator.h

Index: remoting/client/plugin/pepper_port_allocator.h
diff --git a/remoting/client/plugin/pepper_port_allocator.h b/remoting/client/plugin/pepper_port_allocator.h
index c98c242c0091f7b4ae6313d34176463e0a64f78a..76d447bf4858a3498c818770f646dcecacb621e7 100644
--- a/remoting/client/plugin/pepper_port_allocator.h
+++ b/remoting/client/plugin/pepper_port_allocator.h
@@ -8,6 +8,7 @@
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_ptr.h"
 #include "ppapi/cpp/instance_handle.h"
+#include "remoting/protocol/port_allocator_factory.h"
 #include "third_party/webrtc/p2p/client/httpportallocator.h"
 
 namespace remoting {
@@ -47,6 +48,20 @@ class PepperPortAllocator : public cricket::HttpPortAllocatorBase {
   DISALLOW_COPY_AND_ASSIGN(PepperPortAllocator);
 };
 
+class PepperPortAllocatorFactory : public protocol::PortAllocatorFactory {
+ public:
+  PepperPortAllocatorFactory(const pp::InstanceHandle& instance);
+  ~PepperPortAllocatorFactory() override;
+
+   // PortAllocatorFactory interface.
+  scoped_ptr<cricket::HttpPortAllocatorBase> CreatePortAllocator() override;
+
+ private:
+  pp::InstanceHandle instance_;
+
+  DISALLOW_COPY_AND_ASSIGN(PepperPortAllocatorFactory);
+};
+
 }  // namespace remoting
 
 #endif  // REMOTING_CLIENT_PLUGIN_PEPPER_PORT_ALLOCATOR_H_