[PATCH v3 1/3] d2d1: Implement ID2D1Bitmap1::Map().

[Nikolay Sivov]

I started by extending tests from patch 3/3, and I'm curious now how 
does your application create such bitmap?

Is it just 
ID2D1DeviceContext::CreateBitmap(D2D1_BITMAP_OPTIONS_CANNOT_DRAW | 
D2D1_BITMAP_OPTIONS_CPU_READ), or something more complicated?

How is this bitmap used later? Is it set to an image brush, and then 
used for fills?