Indicating sourceType while invoking getUserMedia().

Dear All,

I suggest to add one more argument as parameter to getUserMedia to identify
the type of input device and prompt the permission accordingly.

getUserMedia(constrints, success, failure, *sourceType*)

sourceType can be an enum which represents the type of source like
sourceType
{
    liveSource,
    staticSource
};

Based on the type of source the user should get the prompt for permission
like,

Do you want to allow camera to access
If the user allows, it displays the list of cameras
or
Do you want to allow file system to access.
If the user allows, it displays the window to access file system and select
the required file.

Comments and Suggestions welcome.

Thanks,
Kiran.