Ctegory header should be shown when content of it expanded

#### Purpose

1. Unnecessary jumps when user expands category. For more details take a look on video attached to task [MAGN-5494](http://adsk-oss.myjetbrains.com/youtrack/issue/MAGN-5494).
2. Fix bug. First click on category scrolls up instead of opening category. This bug also can be seen on the video in task MAGN-5494.

Video after fix can be found in comment of specified above task.

#### Modifications

To show category  expander used function `BringIntoView()` with parameters.

#### Additional references

[MAGN-5494](http://adsk-oss.myjetbrains.com/youtrack/issue/MAGN-5494).
[MAGN-5495](http://adsk-oss.myjetbrains.com/youtrack/issue/MAGN-5495).

#### Reviewers

@Benglin, please, take a look.