WME: 1-pixel width sprite becomes a big rectangle is rotation is applied

[lolbot-iichan]

Discovered this issue at FoxTail game, where grandmother have a mechanical clock, which is displayed normally in original game, but looks like 2 giant rectangles in ScummVM instead.

I have exctacted clock's source code and made a simple test game to demonstrate this issue without running FoxTail which is not fully supported by ScummVM yet: ​https://github.com/tobiatesan/wme_testsuite/tree/master/time_test/packages

Screenshots are attached.

Tested on latest ScummVM from dev branch and ScummVM 2.1.0git3428-gc518691d7c (Aug 12 2018 19:04:49).

[lolbot-iichan]

See ​https://github.com/scummvm/scummvm/pull/1665 pull request

[Filippos Karapetis <bluegr@…>]

In fa4d310:

WINTERMUTE: Do not optimize out alpha blits on rotation

This fixes defect #10684: 1-pixel width sprite becomes a big rectangle
if rotation is applied.

Case was originally reproduced with FoxTail game for WME, then reduced
to testcase
​https://github.com/tobiatesan/wme_testsuite/tree/master/time_test/packages