Document the API level required for using video output.

When deploying an Android application containing a QCamerViewfinder widget to show preview from camera on a device with API level 10 (ZTE Crescent), in application output I get "W/dalvikvm( 5112): Unable to resolve superclass of Lorg/qtproject/qt5/android/multimedia/QtSurfaceTexture; (11)" The application does start, but the viewfinder widget does not show.

The whole output is:

Starting remote process.D/dalvikvm( 5112): DexOpt: — END 'QtAndroid.jar' (success) —
D/dalvikvm( 5112): DEX prep '/data/local/tmp/qt/jar/QtAndroid.jar': unzip in 21ms, rewrite 138ms
D/dalvikvm( 5112): DexOpt: — BEGIN 'QtAndroidAccessibility.jar' (bootstrap=0) —
D/dalvikvm( 5112): DexOpt: — END 'QtAndroidAccessibility.jar' (success) —
D/dalvikvm( 5112): DEX prep '/data/local/tmp/qt/jar/QtAndroidAccessibility.jar': unzip in 1ms, rewrite 45ms
D/dalvikvm( 5112): DexOpt: — BEGIN 'QtMultimedia.jar' (bootstrap=0) —
D/dalvikvm( 5112): DexOpt: — END 'QtMultimedia.jar' (success) —
D/dalvikvm( 5112): DEX prep '/data/local/tmp/qt/jar/QtMultimedia.jar': unzip in 3ms, rewrite 66ms
D/dalvikvm( 5112): Trying to load lib /data/local/tmp/qt/lib/libgnustl_shared.so 0x2afd8b80
D/dalvikvm( 5112): Added shared lib /data/local/tmp/qt/lib/libgnustl_shared.so 0x2afd8b80
D/dalvikvm( 5112): No JNI_OnLoad found in /data/local/tmp/qt/lib/libgnustl_shared.so 0x2afd8b80, skipping init
D/dalvikvm( 5112): Trying to load lib /data/local/tmp/qt/lib/libQt5Core.so 0x2afd8b80
D/dalvikvm( 5112): Added shared lib /data/local/tmp/qt/lib/libQt5Core.so 0x2afd8b80
D/dalvikvm( 5112): Trying to load lib /data/local/tmp/qt/lib/libQt5Gui.so 0x2afd8b80
D/dalvikvm( 5112): Added shared lib /data/local/tmp/qt/lib/libQt5Gui.so 0x2afd8b80
D/dalvikvm( 5112): No JNI_OnLoad found in /data/local/tmp/qt/lib/libQt5Gui.so 0x2afd8b80, skipping init
D/dalvikvm( 5112): Trying to load lib /data/local/tmp/qt/lib/libQt5Network.so 0x2afd8b80
D/dalvikvm( 5112): Added shared lib /data/local/tmp/qt/lib/libQt5Network.so 0x2afd8b80
I/Qt ( 5112): Network start
D/dalvikvm( 5112): Trying to load lib /data/local/tmp/qt/lib/libQt5Multimedia.so 0x2afd8b80
D/dalvikvm( 5112): Added shared lib /data/local/tmp/qt/lib/libQt5Multimedia.so 0x2afd8b80
D/dalvikvm( 5112): No JNI_OnLoad found in /data/local/tmp/qt/lib/libQt5Multimedia.so 0x2afd8b80, skipping init
D/dalvikvm( 5112): Trying to load lib /data/local/tmp/qt/lib/libQt5Widgets.so 0x2afd8b80
D/dalvikvm( 5112): Added shared lib /data/local/tmp/qt/lib/libQt5Widgets.so 0x2afd8b80
D/dalvikvm( 5112): No JNI_OnLoad found in /data/local/tmp/qt/lib/libQt5Widgets.so 0x2afd8b80, skipping init
D/dalvikvm( 5112): Trying to load lib /data/local/tmp/qt/lib/libQt5OpenGL.so 0x2afd8b80
D/dalvikvm( 5112): Added shared lib /data/local/tmp/qt/lib/libQt5OpenGL.so 0x2afd8b80
D/dalvikvm( 5112): No JNI_OnLoad found in /data/local/tmp/qt/lib/libQt5OpenGL.so 0x2afd8b80, skipping init
D/dalvikvm( 5112): Trying to load lib /data/local/tmp/qt/lib/libQt5MultimediaWidgets.so 0x2afd8b80
D/dalvikvm( 5112): Added shared lib /data/local/tmp/qt/lib/libQt5MultimediaWidgets.so 0x2afd8b80
D/dalvikvm( 5112): No JNI_OnLoad found in /data/local/tmp/qt/lib/libQt5MultimediaWidgets.so 0x2afd8b80, skipping init
D/dalvikvm( 5112): Trying to load lib /data/local/tmp/qt/plugins/platforms/android/libqtforandroidGL.so 0x2afd8b80
D/dalvikvm( 5112): Added shared lib /data/local/tmp/qt/plugins/platforms/android/libqtforandroidGL.so 0x2afd8b80
I/Qt ( 5112): qt start
W/dalvikvm( 5112): dvmFindClassByName rejecting 'org/qtproject/qt5/android/QtMessageDialogHelper'
D/dalvikvm( 5112): Trying to load lib /data/local/tmp/qt/plugins/mediaservice/libqtmedia_android.so 0x2afd8b80
D/dalvikvm( 5112): Added shared lib /data/local/tmp/qt/plugins/mediaservice/libqtmedia_android.so 0x2afd8b80
W/dalvikvm( 5112): Unable to resolve superclass of Lorg/qtproject/qt5/android/multimedia/QtSurfaceTexture; (11)
W/dalvikvm( 5112): Link of class 'Lorg/qtproject/qt5/android/multimedia/QtSurfaceTexture;' failed
D/dalvikvm( 5112): Trying to load lib /data/data/org.qtproject.example.Test17/lib/libTest17.so 0x2afc4398
D/dalvikvm( 5112): Added shared lib /data/data/org.qtproject.example.Test17/lib/libTest17.so 0x2afc4398
D/dalvikvm( 5112): No JNI_OnLoad found in /data/data/org.qtproject.example.Test17/lib/libTest17.so 0x2afc4398, skipping init
W/dalvikvm( 5112): dvmFindClassByName rejecting 'org/qtproject/qt5/android/QtNativeInputConnection'
W/dalvikvm( 5112): dvmFindClassByName rejecting 'org/qtproject/qt5/android/QtExtractedText'
D/ActivityThread( 5112): <<< done: 100
D/libEGL ( 5112): loaded /system/lib/egl/libGLES_android.so
E/ActivityThread( 5112): >>> handling: 118
D/libEGL ( 5112): loaded /system/lib/egl/libEGL_adreno200.so
D/ActivityThread( 5112): <<< done: 118
D/libEGL ( 5112): loaded /system/lib/egl/libGLESv1_CM_adreno200.so
D/libEGL ( 5112): loaded /system/lib/egl/libGLESv2_adreno200.so
E/ActivityThread( 5112): >>> handling: 125
D/ActivityThread( 5112): <<< done: 125
W/dalvikvm( 5112): VFY: unable to find class referenced in signature (Landroid/graphics/SurfaceTexture
I/dalvikvm( 5112): Could not find method android.hardware.Camera.setPreviewTexture, referenced from method org.qtproject.qt5.android.multimedia.QtCamera.setPreviewTexture
W/dalvikvm( 5112): VFY: unable to resolve virtual method 19: Landroid/hardware/Camera;.setPreviewTexture (Landroid/graphics/SurfaceTexture;)V
D/dalvikvm( 5112): VFY: replacing opcode 0x6e at 0x0002
D/dalvikvm( 5112): GetMethodID: method not found: Landroid/hardware/Camera;.startFaceDetection)V
E/ActivityThread( 5112): >>> handling: 102
D/ActivityThread( 5112): <<< done: 102
E/ActivityThread( 5112): >>> handling: 109

'org.qtproject.example.Test17' died.