New camera viewfinder settings API.

There already was a control interface for the viewfinder settings
but no real public C++ API and a partial QML API.

This patch adds a new C++ API and improves the QML API.

Supported viewfinder settings are resolution, minimumFrameRate,
maximumFrameRate and pixelFormat. The camera can be queried for
the supported values for each of these settings.

A new control interface was created to match the new API.

Change-Id: I289fea038fe46277a5516c956a64280da09ed985
Reviewed-by: Andrew den Exter <andrew.den.exter@qinetic.com.au>

src/multimedia/camera/qcamera_p.h

@@ -56,6 +56,8 @@ class QCameraControl;
 class QVideoDeviceSelectorControl;
 class QCameraLocksControl;
 class QCameraInfoControl;
+class QCameraViewfinderSettingsControl;
+class QCameraViewfinderSettingsControl2;
 
 class QCameraPrivate : public QMediaObjectPrivate
 {
@@ -68,6 +70,8 @@ public:
         deviceControl(0),
         locksControl(0),
         infoControl(0),
+        viewfinderSettingsControl(0),
+        viewfinderSettingsControl2(0),
         viewfinder(0),
         capture(0),
         state(QCamera::UnloadedState),
@@ -91,6 +95,8 @@ public:
     QVideoDeviceSelectorControl *deviceControl;
     QCameraLocksControl *locksControl;
     QCameraInfoControl *infoControl;
+    QCameraViewfinderSettingsControl *viewfinderSettingsControl;
+    QCameraViewfinderSettingsControl2 *viewfinderSettingsControl2;
 
     QCameraExposure *cameraExposure;
     QCameraFocus *cameraFocus;