Summary:
There are two cases where black spots appear on opaque azalea leaves and flowering azalea leaves. Other leaves do not have this issue.

Steps to Reproduce:
     ^{Case 1}

1. Go to Settings > Video
2. Enable Fancy Leaves
3. Set the render distance to 8 chunks (not required, but is most noticeable with 8 chunks)
4. Build a wall out of azalea leaves
5. Move away from the leaves until they turn opaque

     ^{Case 2}

1. Go to Settings > Video
2. Enable Fancy Leaves
3. Disable Fancy Graphics
4. Hold or drop azalea leaves

Observed Results:
Black spots appear on the azalea leaves.

Expected Results:
The black spots should be dark green, just like other leaves.

Screenshots: