[win] Create ModuleDatabase and ModuleEventSinkImpl.

chrome/browser/conflicts/module_database_impl_win.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 "chrome/browser/conflicts/module_database_impl_win.h"
+
+#include "chrome/browser/conflicts/module_database_win.h"
+#include "content/public/browser/browser_thread.h"
+#include "mojo/public/cpp/bindings/strong_binding.h"
+
+ModuleDatabaseImpl::ModuleDatabaseImpl(::ModuleDatabase* module_database)
+    : module_database_(module_database), process_id_(0) {}
+
+ModuleDatabaseImpl::~ModuleDatabaseImpl() = default;
+
+// static
+void ModuleDatabaseImpl::Create(::ModuleDatabase* module_database,
+                                mojom::ModuleDatabaseRequest request) {
+  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+  std::unique_ptr<ModuleDatabaseImpl> module_database_impl =
+      base::WrapUnique(new ModuleDatabaseImpl(module_database));

[grt (UTC plus 2), 2016/12/15 09:07:12]

base::MakeUnique<ModuleDatabaseImpl>(module_database)

and #include "base/memory/ptr_util.h"

[chrisha, 2016/12/19 20:15:36]

Done.

+  base::Closure error_handler =
+      base::Bind(&ModuleDatabaseImpl::OnProcessEnded,

[grt (UTC plus 2), 2016/12/15 09:07:12]

#include "base/bind.h"
#include "base/callback.h"

[chrisha, 2016/12/19 20:15:36]

bind.h I get, but why callback.h? I don't make use of base::Callback anywhere in
this file?

+                 base::Unretained(module_database_impl.get()));
+  auto binding = mojo::MakeStrongBinding(std::move(module_database_impl),
+                                         std::move(request));
+  binding->set_connection_error_handler(error_handler);
+}
+
+void ModuleDatabaseImpl::OnProcessStarted(uint32_t process_id,
+                                          uint32_t process_type) {
+  // This should only be called once, and it should be the first message
+  // received.
+  DCHECK_EQ(0u, process_id_);

[sky, 2016/12/14 21:58:08]

Won't a misbehaving client cause problems here? Whoever you have review this
should consider this from a security perspective.

[chrisha, 2016/12/19 20:15:36]

The ModuleDatabase itself is robust to misuse, as noted in its comments.

I was torn between making this class itself robust (as it simply forwards
existing messages, although with some extra adornment), or simply documenting
the expected use via DCHECKs. I'll talk to security about best practices here.

+  process_id_ = process_id;

[sky, 2016/12/14 21:58:08]

DCHECK_NE(0u, process_id_);

[chrisha, 2016/12/19 20:15:36]

Done.

+  module_database_->OnProcessStarted(
+      process_id, static_cast<content::ProcessType>(process_type));

[sky, 2016/12/14 21:58:08]

You need to valid process_type.

[chrisha, 2016/12/19 20:15:36]

Done.

+}
+
+void ModuleDatabaseImpl::OnModuleEvent(mojom::ModuleEventPtr module_event) {
+  // This should only be called after OnProcessStarted has been called.
+  DCHECK_NE(0u, process_id_);
+  module_database_->OnModuleEvent(process_id_, *module_event.get());
+}
+
+void ModuleDatabaseImpl::OnProcessEnded() {
+  // This should only be called after OnProcessStarted has been called.
+  DCHECK_NE(0u, process_id_);
+  module_database_->OnProcessEnded(process_id_);
+}