[Extensions Bindings] Notify of event unregistration on invalidation

extensions/renderer/api_bindings_system_unittest.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "extensions/renderer/api_bindings_system.h"
 
 #include "base/bind.h"
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
 #include "base/stl_util.h"
@@ skipping 104 matching lines @@
         base::Bind(&APIBindingsSystemTestBase::GetAPISchema,
                    base::Unretained(this)),
         base::Bind(&APIBindingsSystemTestBase::OnAPIRequest,
                    base::Unretained(this)),
         base::Bind(&APIBindingsSystemTestBase::OnEventListenersChanged,
                    base::Unretained(this)),
         APILastError(APILastError::GetParent()));
   }
 
   void TearDown() override {
+    {
+      v8::HandleScope handle_scope(isolate());
+      bindings_system_->WillReleaseContext(ContextLocal());
+    }
     bindings_system_.reset();
     APIBindingTest::TearDown();
   }
 
   // Checks that |last_request_| exists and was provided with the
   // |expected_name| and |expected_arguments|.
   void ValidateLastRequest(const std::string& expected_name,
                            const std::string& expected_arguments);
 
   const APIRequestHandler::Request* last_request() const {
@@ skipping 447 matching lines @@
                                                        context, "idleState"));
     bindings_system()->FireEventInContext("idle.onStateChanged", context,
                                           *ListValueFromString("['active']"));
 
     EXPECT_EQ("\"active\"", GetStringPropertyFromObject(context->Global(),
                                                         context, "idleState"));
   }
 }
 
 }  // namespace extensions