AppShell: Create input method and handle key events

extensions/shell/browser/input_method_event_handler.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/shell/browser/input_method_event_handler.h"
+
+#include "ui/base/ime/input_method.h"
+#include "ui/events/event.h"
+
+namespace extensions {
+
+InputMethodEventHandler::InputMethodEventHandler(ui::InputMethod* input_method)
+    : input_method_(input_method), post_ime_(false) {}

[James Cook, 2016/12/16 19:00:50]

nit: DCHECK(input_method_) so it's self documenting that input_method can't be
null

(I'm trying to encourage people to do this sort of thing. I love preconditions.
:-)

[michaelpg, 2016/12/17 03:07:46]

Done.

+
+InputMethodEventHandler::~InputMethodEventHandler() {}
+
+void InputMethodEventHandler::set_post_ime(bool post_ime) {
+  post_ime_ = post_ime;
+}
+
+void InputMethodEventHandler::OnKeyEvent(ui::KeyEvent* event) {
+  // Ignore events being dispatched back to the delegate from the input method.
+  if (post_ime_)
+    return;
+
+  if (event->flags() & ui::EF_IS_SYNTHESIZED)
+    return;
+
+  input_method_->DispatchKeyEvent(event);
+  event->StopPropagation();
+}
+
+}  // namespace extensions