Replacing most of web_task.h with base::Closure + base::WeakPtrFactory.

components/test_runner/mock_web_midi_accessor.cc

Index: components/test_runner/mock_web_midi_accessor.cc
diff --git a/components/test_runner/mock_web_midi_accessor.cc b/components/test_runner/mock_web_midi_accessor.cc
index f5920bd530e5f215c1241f8efdf832b38f8a96d3..b53915b4b37d9ee8e51312874e5a1bc84004a25f 100644
--- a/components/test_runner/mock_web_midi_accessor.cc
+++ b/components/test_runner/mock_web_midi_accessor.cc
@@ -4,43 +4,22 @@
 
 #include "components/test_runner/mock_web_midi_accessor.h"
 
+#include "base/bind.h"
+#include "base/bind_helpers.h"
 #include "base/macros.h"
 #include "components/test_runner/test_interfaces.h"
 #include "components/test_runner/test_runner.h"
+#include "components/test_runner/web_task.h"
 #include "components/test_runner/web_test_delegate.h"
 #include "components/test_runner/web_test_runner.h"
+#include "third_party/WebKit/public/platform/WebString.h"
 #include "third_party/WebKit/public/platform/modules/webmidi/WebMIDIAccessorClient.h"
 
 namespace test_runner {
 
-namespace {
-
-class DidStartSessionTask : public WebMethodTask<MockWebMIDIAccessor> {
- public:
-  DidStartSessionTask(MockWebMIDIAccessor* object,
-                      blink::WebMIDIAccessorClient* client,
-                      bool result)
-      : WebMethodTask<MockWebMIDIAccessor>(object),
-        client_(client),
-        result_(result) {}
-
-  void RunIfValid() override {
-    client_->didStartSession(result_, "InvalidStateError", "");
-  }
-
- private:
-  blink::WebMIDIAccessorClient* client_;
-  bool result_;
-
-  DISALLOW_COPY_AND_ASSIGN(DidStartSessionTask);
-};
-
-}  // namespace
-
 MockWebMIDIAccessor::MockWebMIDIAccessor(blink::WebMIDIAccessorClient* client,
                                          TestInterfaces* interfaces)
-    : client_(client), interfaces_(interfaces) {
-}
+    : client_(client), interfaces_(interfaces), weak_factory_(this) {}
 
 MockWebMIDIAccessor::~MockWebMIDIAccessor() {
 }
@@ -59,8 +38,13 @@ void MockWebMIDIAccessor::startSession() {
                             "MockOutputName",
                             "MockOutputVersion",
                             state);
-  interfaces_->GetDelegate()->PostTask(new DidStartSessionTask(
-      this, client_, interfaces_->GetTestRunner()->midiAccessorResult()));
+  interfaces_->GetDelegate()->PostTask(new WebCallbackTask(base::Bind(
+      &MockWebMIDIAccessor::ReportStartedSession, weak_factory_.GetWeakPtr(),
+      interfaces_->GetTestRunner()->midiAccessorResult())));
+}
+
+void MockWebMIDIAccessor::ReportStartedSession(bool success) {
+  client_->didStartSession(success, "InvalidStateError", "");
 }
 
 void MockWebMIDIAccessor::sendMIDIData(unsigned port_index,