BUG: DatetimeIndex slicing with boolean Index raises TypeError
- [x] closes #22533
- [x] tests added / passed
- [x] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [x] whatsnew entry

Hello @sinhrks! Thanks for updating the PR.

 - There are no PEP8 issues in the file [`pandas/core/arrays/datetimelike.py`](https://github.com/sinhrks/pandas/blob/9c756b6e989458a06ae7e5b3f6fff6d91cb0529a/pandas/core/arrays/datetimelike.py) !

 - There are no PEP8 issues in the file [`pandas/core/indexes/base.py`](https://github.com/sinhrks/pandas/blob/9c756b6e989458a06ae7e5b3f6fff6d91cb0529a/pandas/core/indexes/base.py) !

 - There are no PEP8 issues in the file [`pandas/core/indexes/multi.py`](https://github.com/sinhrks/pandas/blob/9c756b6e989458a06ae7e5b3f6fff6d91cb0529a/pandas/core/indexes/multi.py) !

 - There are no PEP8 issues in the file [`pandas/tests/indexes/datetimes/test_indexing.py`](https://github.com/sinhrks/pandas/blob/9c756b6e989458a06ae7e5b3f6fff6d91cb0529a/pandas/tests/indexes/datetimes/test_indexing.py) !

 - There are no PEP8 issues in the file [`pandas/tests/indexes/multi/test_indexing.py`](https://github.com/sinhrks/pandas/blob/9c756b6e989458a06ae7e5b3f6fff6d91cb0529a/pandas/tests/indexes/multi/test_indexing.py) !

 - There are no PEP8 issues in the file [`pandas/tests/indexes/test_base.py`](https://github.com/sinhrks/pandas/blob/9c756b6e989458a06ae7e5b3f6fff6d91cb0529a/pandas/tests/indexes/test_base.py) !

 - There are no PEP8 issues in the file [`pandas/tests/indexes/test_numeric.py`](https://github.com/sinhrks/pandas/blob/9c756b6e989458a06ae7e5b3f6fff6d91cb0529a/pandas/tests/indexes/test_numeric.py) !



##### Comment last updated on September 27, 2018 at 09:07 Hours UTC # [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/22852?src=pr&el=h1) Report
> Merging [#22852](https://codecov.io/gh/pandas-dev/pandas/pull/22852?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/528527b20f085524f484fef70dcde3c0b051782b?src=pr&el=desc) will **not change** coverage.
> The diff coverage is `100%`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/22852/graphs/tree.svg?width=650&token=eZ4WkYLtcO&height=150&src=pr)](https://codecov.io/gh/pandas-dev/pandas/pull/22852?src=pr&el=tree)

```diff
@@           Coverage Diff           @@
##           master   #22852   +/-   ##
=======================================
  Coverage   92.25%   92.25%           
=======================================
  Files         161      161           
  Lines       51207    51207           
=======================================
  Hits        47239    47239           
  Misses       3968     3968
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `90.63% <100%> (ø)` | :arrow_up: |
| #single | `42.28% <100%> (ø)` | :arrow_up: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/22852?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/core/arrays/datetimelike.py](https://codecov.io/gh/pandas-dev/pandas/pull/22852/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvYXJyYXlzL2RhdGV0aW1lbGlrZS5weQ==) | `96.16% <100%> (ø)` | :arrow_up: |
| [pandas/core/indexes/multi.py](https://codecov.io/gh/pandas-dev/pandas/pull/22852/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvaW5kZXhlcy9tdWx0aS5weQ==) | `95.46% <100%> (ø)` | :arrow_up: |
| [pandas/core/indexes/base.py](https://codecov.io/gh/pandas-dev/pandas/pull/22852/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvaW5kZXhlcy9iYXNlLnB5) | `96.45% <100%> (ø)` | :arrow_up: |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/22852?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/22852?src=pr&el=footer). Last update [528527b...420e5c4](https://codecov.io/gh/pandas-dev/pandas/pull/22852?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
 lgtm. ping on green. @WillAyd over to you. can you merge master and ping on green. thanks @sinhrks 