This has been reported already in 1.4.1 (MC-12), and it has been closed, with the reasoning that picking the block was only a creative mode feature, and have not this block in the creative inventory. Now, that this feature is also a survival mode one, and you can have this item in survival, I think it should be fixed.
MC-120405
Pick Block with Mushroom Blocks
Resolved
Duplicate
0
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