Enable keyboard filters in PNaCl client

remoting/client/plugin/normalizing_input_filter_cros.h

Index: remoting/client/plugin/normalizing_input_filter_cros.h
diff --git a/remoting/client/plugin/normalizing_input_filter_cros.h b/remoting/client/plugin/normalizing_input_filter_cros.h
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+++ b/remoting/client/plugin/normalizing_input_filter_cros.h
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+// 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 "remoting/protocol/input_filter.h"
+
+#include "remoting/proto/event.pb.h"
+
+namespace remoting {
+
+// NormalizingInputFilterCros addresses the problems generated by key rewritings
+// such as Down->PageDown, 1->F1, etc, when keys are pressed in combination with
+// the OSKey (aka Search). Rewriting OSKey+Down, for example, causes us to
+// receive the following:
+//
+// keydown OSKey
+// keydown PageDown
+// keyup PageDown
+// keyup OSKey
+//
+// The host system will therefore behave as if OSKey+PageDown were pressed,
+// rather than PageDown alone.
+class NormalizingInputFilterCros : public protocol::InputFilter {
+ public:
+  explicit NormalizingInputFilterCros(protocol::InputStub* input_stub);
+  virtual ~NormalizingInputFilterCros();
+
+  // InputFilter overrides.
+  virtual void InjectKeyEvent(const protocol::KeyEvent& event) OVERRIDE;
+  virtual void InjectMouseEvent(const protocol::MouseEvent& event) OVERRIDE;
+
+ private:
+  void ProcessKeyDown(const protocol::KeyEvent& event);
+  void ProcessKeyUp(const protocol::KeyEvent& event);
+
+  void SwitchRewritingKeyToModifying();
+
+  // Holds the keydown event for the most recent OSKey to have been pressed,
+  // while it is Rewriting, or we are not yet sure whether it is Normal,
+  // Rewriting or Modifying. The event is sent on if we switch to Modifying, or
+  // discarded if the OSKey is released while in Rewriting mode.
+  protocol::KeyEvent deferred_keydown_event_;
+
+  // True while the |rewrite_keydown_event_| key is Rewriting, i.e. was followed
+  // by one or more Rewritten key events, and not by any Modified events.
+  bool deferred_key_is_rewriting_;
+
+  // Stores the code of the OSKey while it is pressed for use as a Modifier.
+  uint32 modifying_key_;
+
+  DISALLOW_COPY_AND_ASSIGN(NormalizingInputFilterCros);
+};
+
+}  // namespace remoting