Add FlushForTesting to InterfacePtr and Binding.

mojo/public/cpp/bindings/lib/control_message_proxy.cc

Index: mojo/public/cpp/bindings/lib/control_message_proxy.cc
diff --git a/mojo/public/cpp/bindings/lib/control_message_proxy.cc b/mojo/public/cpp/bindings/lib/control_message_proxy.cc
index 06d9815bc08ba8a6fcfb4741579d60b9a8cd81c8..79da7d8971b34bea6bdd80d425975984f51a154b 100644
--- a/mojo/public/cpp/bindings/lib/control_message_proxy.cc
+++ b/mojo/public/cpp/bindings/lib/control_message_proxy.cc
@@ -10,6 +10,7 @@
 
 #include "base/bind.h"
 #include "base/macros.h"
+#include "base/run_loop.h"
 #include "mojo/public/cpp/bindings/lib/message_builder.h"
 #include "mojo/public/cpp/bindings/lib/serialization.h"
 #include "mojo/public/cpp/bindings/message.h"
@@ -95,12 +96,19 @@ void RunVersionCallback(
   callback.Run(version);
 }
 
+void RunClosure(const base::Closure& callback,
+                interface_control::RunResponseMessageParamsPtr run_response) {
+  callback.Run();
+}
+
 }  // namespace
 
 ControlMessageProxy::ControlMessageProxy(MessageReceiverWithResponder* receiver)
     : receiver_(receiver) {
 }
 
+ControlMessageProxy::~ControlMessageProxy() = default;
+
 void ControlMessageProxy::QueryVersion(
     const base::Callback<void(uint32_t)>& callback) {
   auto input_ptr = interface_control::RunInput::New();
@@ -117,5 +125,30 @@ void ControlMessageProxy::RequireVersion(uint32_t version) {
   SendRunOrClosePipeMessage(receiver_, std::move(input_ptr), &context_);
 }
 
+void ControlMessageProxy::FlushForTesting() {
+  auto input_ptr = interface_control::RunInput::New();
+  input_ptr->set_flush_for_testing(interface_control::FlushForTesting::New());
+  base::RunLoop run_loop;
+  run_loop_quit_closure_ = run_loop.QuitClosure();
+  SendRunMessage(
+      receiver_, std::move(input_ptr),
+      base::Bind(&RunClosure,
+                 base::Bind(&ControlMessageProxy::RunFlushForTestingClosure,
+                            base::Unretained(this))),
+      &context_);
+  run_loop.Run();
+}
+
+void ControlMessageProxy::RunFlushForTestingClosure() {
+  DCHECK(!run_loop_quit_closure_.is_null());
+  run_loop_quit_closure_.Run();
+  run_loop_quit_closure_.Reset();
+}
+
+void ControlMessageProxy::OnConnectionError() {
+  if (!run_loop_quit_closure_.is_null())
+    RunFlushForTestingClosure();
+}
+
 }  // namespace internal
 }  // namespace mojo