winrt: Add camera service

This adds a basic camera service with viewfinder (video renderer based),
still image capture, and device selection support.

Runtime apps must set the "webcam" and "microphone" device capabilities
in order to access the hardware. This can be done by adding the following
to the .pro file:
    WINRT_MANIFEST.capabilites_device += webcam microphone

[ChangeLog] Enabled basic camera support in the winrt backend.

Change-Id: If4f963ef645d93c757ae23aec9a9c8aae122324f
Reviewed-by: Yoann Lopes <yoann.lopes@digia.com>

src/plugins/winrt/qwinrtcameracontrol.h

@@ -0,0 +1,111 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
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+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
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+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
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+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
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+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QWINRTCAMERACONTROL_H
+#define QWINRTCAMERACONTROL_H
+
+#include <QtMultimedia/QCameraControl>
+#include <QtCore/qt_windows.h>
+
+namespace ABI {
+    namespace Windows {
+        namespace Media {
+            namespace Capture {
+                struct IMediaCapture;
+                struct IMediaCaptureFailedEventArgs;
+            }
+        }
+        namespace Foundation {
+            struct IAsyncAction;
+            enum class AsyncStatus;
+        }
+    }
+}
+
+QT_BEGIN_NAMESPACE
+
+class QVideoRendererControl;
+class QVideoDeviceSelectorControl;
+class QCameraImageCaptureControl;
+
+class QWinRTCameraControlPrivate;
+class QWinRTCameraControl : public QCameraControl
+{
+    Q_OBJECT
+public:
+    explicit QWinRTCameraControl(QObject *parent = 0);
+    ~QWinRTCameraControl();
+
+    QCamera::State state() const Q_DECL_OVERRIDE;
+    void setState(QCamera::State state) Q_DECL_OVERRIDE;
+
+    QCamera::Status status() const Q_DECL_OVERRIDE;
+
+    QCamera::CaptureModes captureMode() const Q_DECL_OVERRIDE;
+    void setCaptureMode(QCamera::CaptureModes mode) Q_DECL_OVERRIDE;
+    bool isCaptureModeSupported(QCamera::CaptureModes mode) const Q_DECL_OVERRIDE;
+
+    bool canChangeProperty(PropertyChangeType changeType, QCamera::Status status) const Q_DECL_OVERRIDE;
+
+    QVideoRendererControl *videoRenderer() const;
+    QVideoDeviceSelectorControl *videoDeviceSelector() const;
+    QCameraImageCaptureControl *imageCaptureControl() const;
+
+    ABI::Windows::Media::Capture::IMediaCapture *handle() const;
+    QSize imageSize() const;
+
+private slots:
+    void onBufferRequested();
+
+private:
+    HRESULT enumerateDevices();
+    HRESULT initialize();
+    HRESULT onCaptureFailed(ABI::Windows::Media::Capture::IMediaCapture *,
+                            ABI::Windows::Media::Capture::IMediaCaptureFailedEventArgs *);
+    HRESULT onRecordLimitationExceeded(ABI::Windows::Media::Capture::IMediaCapture *);
+
+    QScopedPointer<QWinRTCameraControlPrivate> d_ptr;
+    Q_DECLARE_PRIVATE(QWinRTCameraControl)
+};
+
+QT_END_NAMESPACE
+
+#endif // QWINRTCAMERACONTROL_H