Convert KeyboardDrivenEventRewriter to a ui::EventRewriter.

chrome/browser/chromeos/events/event_rewriter_controller.cc

+// Copyright 2014 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/chromeos/events/event_rewriter_controller.h"
+
+#include "ash/shell.h"
+#include "ui/aura/window_tree_host.h"
+#include "ui/events/event_source.h"
+
+namespace chromeos {
+
+EventRewriterController::EventRewriterController() : operational_(false) {
+}
+
+EventRewriterController::~EventRewriterController() {
+  Shutdown();
+}
+
+void EventRewriterController::AddEventRewriter(
+    scoped_ptr<ui::EventRewriter> rewriter) {
+  DCHECK(!operational_);
+  rewriters_.push_back(rewriter.release());
+}
+
+void EventRewriterController::Init() {
+  DCHECK(!operational_);
+  operational_ = true;
+  // Add the rewriters to each existing root window EventSource.
+  aura::Window::Windows windows = ash::Shell::GetAllRootWindows();
+  for (aura::Window::Windows::iterator it = windows.begin();
+       it != windows.end();
+       ++it) {
+    AddToEventSource((*it)->GetHost()->GetEventSource());
+  }
+}
+
+void EventRewriterController::Shutdown() {
+  operational_ = false;

[Daniel Erat, 2014/04/28 16:51:55]

is calling AddEventWriter() and Init() again allowed after this point? if not,
i'd prefer that you got rid of the public Shutdown() method (also uncommon in
chrome, apart from in singleton objects) and instead did cleanup in the d'tor:

  ERC::~ERC() {
    // Remove the rewriters from every root window EventSource and destroy them.
    ...
  }

might be clearer to rename |operational_| to |initialized_|, as well.

[kpschoedel, 2014/04/28 17:23:48]

Done.

+  // Remove the rewriters from every root window EventSource and destroy them.
+  for (EventRewriters::iterator rewriter_iter = rewriters_.begin();
+       rewriter_iter != rewriters_.end();
+       ++rewriter_iter) {
+    aura::Window::Windows windows = ash::Shell::GetAllRootWindows();
+    for (aura::Window::Windows::iterator window_iter = windows.begin();
+         window_iter != windows.end();
+         ++window_iter) {
+      (*window_iter)->GetHost()->GetEventSource()->RemoveEventRewriter(
+          *rewriter_iter);
+    }
+  }
+  rewriters_.clear();
+}
+
+void EventRewriterController::OnHostInitialized(aura::WindowTreeHost* host) {
+  if (operational_)
+    AddToEventSource(host->GetEventSource());
+}
+
+void EventRewriterController::AddToEventSource(ui::EventSource* source) {
+  DCHECK(source);
+  for (EventRewriters::iterator it = rewriters_.begin(); it != rewriters_.end();
+       ++it) {
+    source->AddEventRewriter(*it);
+  }
+}
+
+}  // namespace chromeos