Add an extensions keep-alive client.

extensions/renderer/api_test_base.h

Index: extensions/renderer/api_test_base.h
diff --git a/extensions/renderer/api_test_base.h b/extensions/renderer/api_test_base.h
index c9a23e352430281f3eedd1f167157c7415ec0e0a..f5bd0fc94de84e318f15954e1540bc70ca605d96 100644
--- a/extensions/renderer/api_test_base.h
+++ b/extensions/renderer/api_test_base.h
@@ -11,6 +11,7 @@
 
 #include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
+#include "extensions/common/mojo/keep_alive.mojom.h"
 #include "extensions/renderer/module_system_test.h"
 #include "extensions/renderer/v8_schema_registry.h"
 #include "gin/handle.h"
@@ -61,6 +62,28 @@ class TestServiceProvider : public gin::Wrappable<TestServiceProvider> {
       service_factories_;
 };
 
+// A counter for the number of keep alives requested.
+class KeepAliveCounter {

[Ken Rockot(use gerrit already), 2014/10/24 18:29:54]

nit: What do you think about moving KeepAliveCounter and maybe
TestServiceProvider into their own source files? Doing so might also warrant
introducing a new //extensions/renderer/test/ home to keep them separated from
everything else. 

[OR we could invert this and like //content have an //extensions/test/ (and
maybe even subpaths for {browser, common, renderer}), but I don't want to fret
too much over this detail for your CL]

[Sam McNally, 2014/10/27 05:07:24]

TestServiceProvider is fairly tightly coupled to ApiTestBase so I think it's
reasonable for it to live here. Removed KeepAliveCounter.

+ public:
+  KeepAliveCounter();
+
+  void CreateKeepAlive(mojo::InterfaceRequest<KeepAlive> request);
+  void WaitUntilKeepAlivesFinish();
+
+  int keep_alives() { return keep_alives_; }
+  int keep_alive_ends() { return keep_alive_ends_; }
+
+ private:
+  class Instance;
+
+  void PollKeepAlives(const base::Closure& quit_closure);
+
+  int keep_alives_;
+  int keep_alive_ends_;
+
+  DISALLOW_COPY_AND_ASSIGN(KeepAliveCounter);
+};
+
 // A base class for unit testing apps/extensions API custom bindings implemented
 // on Mojo services. To use:
 // 1. Register test Mojo service implementations on service_provider().
@@ -76,6 +99,7 @@ class ApiTestBase : public ModuleSystemTest {
   virtual void SetUp() override;
   void RunTest(const std::string& file_name, const std::string& test_name);
   TestServiceProvider* service_provider() { return service_provider_; }
+  KeepAliveCounter& keep_alive_counter() { return keep_alive_counter_; }
 
  private:
   void RegisterModules();
@@ -87,6 +111,7 @@ class ApiTestBase : public ModuleSystemTest {
   base::MessageLoop message_loop_;
   TestServiceProvider* service_provider_;
   scoped_ptr<V8SchemaRegistry> v8_schema_registry_;
+  KeepAliveCounter keep_alive_counter_;
 };
 
 }  // namespace extensions