Invokes platform specific functionality to allocate a new image.
<p>
<b>IMPORTANT:</b> This method is <em>not</em> part of the public
API for <code>Image</code>. It is marked public only so that it
can be shared within the packages provided by SWT. It is not
available on all platforms, and should never be called from
application code.
</p>
@param device the device on which to allocate the color
@param type the type of the image (<code>SWT.BITMAP</code> or <code>SWT.ICON</code>)
@param pixmap the OS handle for the image
@param mask the OS handle for the image mask
Invokes platform specific functionality to allocate a new image. <p> <b>IMPORTANT:</b> This method is <em>not</em> part of the public API for <code>Image</code>. It is marked public only so that it can be shared within the packages provided by SWT. It is not available on all platforms, and should never be called from application code. </p>
@param device the device on which to allocate the color @param type the type of the image (<code>SWT.BITMAP</code> or <code>SWT.ICON</code>) @param pixmap the OS handle for the image @param mask the OS handle for the image mask
@private