IWYU in Movie.h

SkBitmap.h was being pulled in (transitively) by SkCanvas.h, but that
was removed in Skia's https://skia-review.googlesource.com/15195.
Include SkBitmap.h directly in Movie.h

Test: No change in behavior. No test. Compilation will "test".
Change-Id: Ibeefdf829e4070e41b6dace4b7e63fd9b67870eb