BUG: SparseDataFrame construction with lists not coercing to dtype  (GH 15682)
 - [x] closes #15682
 - [x] tests added / passed
 - [ ] passes ``git diff upstream/master --name-only -- '*.py' | flake8 --diff``
 - [x] whatsnew entry

# [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/15834?src=pr&el=h1) Report
> Merging [#15834](https://codecov.io/gh/pandas-dev/pandas/pull/15834?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/bd169dc0a91f50031f6c2240075ff84d6b296576?src=pr&el=desc) will **decrease** coverage by `0.01%`.
> The diff coverage is `n/a`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/15834/graphs/tree.svg?height=150&width=650&token=eZ4WkYLtcO&src=pr)](https://codecov.io/gh/pandas-dev/pandas/pull/15834?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #15834      +/-   ##
==========================================
- Coverage   90.97%   90.96%   -0.02%     
==========================================
  Files         143      143              
  Lines       49429    49442      +13     
==========================================
+ Hits        44969    44973       +4     
- Misses       4460     4469       +9
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `88.72% <ø> (?)` | |
| #single | `40.69% <ø> (?)` | |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/15834?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/sparse/frame.py](https://codecov.io/gh/pandas-dev/pandas/pull/15834?src=pr&el=tree#diff-cGFuZGFzL3NwYXJzZS9mcmFtZS5weQ==) | `94.26% <ø> (ø)` | :arrow_up: |
| [pandas/io/gbq.py](https://codecov.io/gh/pandas-dev/pandas/pull/15834?src=pr&el=tree#diff-cGFuZGFzL2lvL2dicS5weQ==) | `25% <0%> (-58.34%)` | :arrow_down: |
| [pandas/core/frame.py](https://codecov.io/gh/pandas-dev/pandas/pull/15834?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvZnJhbWUucHk=) | `97.56% <0%> (-0.1%)` | :arrow_down: |
| [pandas/core/categorical.py](https://codecov.io/gh/pandas-dev/pandas/pull/15834?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvY2F0ZWdvcmljYWwucHk=) | `95.85% <0%> (ø)` | :arrow_up: |
| [pandas/core/series.py](https://codecov.io/gh/pandas-dev/pandas/pull/15834?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvc2VyaWVzLnB5) | `94.86% <0%> (ø)` | :arrow_up: |
| [pandas/io/html.py](https://codecov.io/gh/pandas-dev/pandas/pull/15834?src=pr&el=tree#diff-cGFuZGFzL2lvL2h0bWwucHk=) | `84.81% <0%> (+0.32%)` | :arrow_up: |
| [pandas/core/common.py](https://codecov.io/gh/pandas-dev/pandas/pull/15834?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvY29tbW9uLnB5) | `91.3% <0%> (+0.33%)` | :arrow_up: |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/15834?src=pr&el=continue).
> **Legend** - [Click here to learn more](https://docs.codecov.io/docs/codecov-delta)
> `Δ = absolute <relative> (impact)`, `ø = not affected`, `? = missing data`
> Powered by [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/15834?src=pr&el=footer). Last update [bd169dc...04fba8d](https://codecov.io/gh/pandas-dev/pandas/pull/15834?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).