[#19431] Regression in make_block_same_class (tests failing for new fastparquet release)
- [x] closes https://github.com/pandas-dev/pandas/issues/19431
- [x] tests added / passed
- [x] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [x] whatsnew entry

`dtype` seems still in use at:
https://github.com/minggli/pandas/blob/2f4fc0790a5e5c51eb80bbfadf4c80f0bb424c56/pandas/core/internals.py#L2911
# [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/19434?src=pr&el=h1) Report
> :exclamation: No coverage uploaded for pull request base (`master@8cbee35`). [Click here to learn what that means](https://docs.codecov.io/docs/error-reference#section-missing-base-commit).
> The diff coverage is `100%`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/19434/graphs/tree.svg?width=650&height=150&src=pr&token=eZ4WkYLtcO)](https://codecov.io/gh/pandas-dev/pandas/pull/19434?src=pr&el=tree)

```diff
@@            Coverage Diff            @@
##             master   #19434   +/-   ##
=========================================
  Coverage          ?   91.62%           
=========================================
  Files             ?      150           
  Lines             ?    48724           
  Branches          ?        0           
=========================================
  Hits              ?    44642           
  Misses            ?     4082           
  Partials          ?        0
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `89.99% <100%> (?)` | |
| #single | `41.74% <66.66%> (?)` | |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/19434?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/core/internals.py](https://codecov.io/gh/pandas-dev/pandas/pull/19434/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvaW50ZXJuYWxzLnB5) | `95.47% <100%> (ø)` | |

------

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> `Δ = absolute <relative> (impact)`, `ø = not affected`, `? = missing data`
> Powered by [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/19434?src=pr&el=footer). Last update [8cbee35...77422ba](https://codecov.io/gh/pandas-dev/pandas/pull/19434?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
 I am going to merge #19435 before this to fix the CI for now. you should remove the pins (all except the 2.7 one),  and this should still pass (after fixes above). add a whatsnew entry in other api changes for this. (say compat with fp >= 0.1.4) @jorisvandenbossche @jreback please feedback on this PR? @minggli Thanks a lot! (and sorry for the extensive back and forth) @jorisvandenbossche no problem. happy to help! 