Based on Google Analytics error report, the following error happens
occasionally (15% or total errors for 2019-03):
```
Cannot read property '0' of null TypeError: at [email protected]
```
This was a result of calling [ViewportScroller#scrollToPosition()][1]
with `null`, which in turn happens when calling
[ScrollService#scrollToPosition()][2] while `this.scrollPosition` is
`null`. This can be a result of a `popstate` event without an associated
history state.
This commit fixes the error by checking whether `this.scrollPosition` is
`null`, before using it with `scrollToPosition()`.
(It also refactors away the unneeded internal `popStateFired` property.)
[1]: https://github.com/angular/angular/blob/deca6a60d/packages/common/src/viewport_scroller.ts#L101-L105
[2]: https://github.com/angular/angular/blob/deca6a60d/aio/src/app/shared/scroll.service.ts#L158-L161
PR Close#29658
The supposedly visually hidden `mat-icon` creates unnecessary space at
the bottom of the page (below the footer) in recent Chrome versions.
This didn't happen before and it still doesn't happen in other browsers
(Firefox, Edge, IE).
This commit fixes it by wrapping the icon in a visually hidden `div`
container, which doesn't have other styles (such as `mat-icon` does)
that could affect the layout of the page.
Fixes#28858
PR Close#28864
There is no debouncing when we store the scroll Position.
Currently, we have a message in the console after a while:
>Throttling history state changes to prevent the browser from hanging
see: https://bugs.chromium.org/p/chromium/issues/detail?id=786211 for more informations
PR Close#28368
Currently, when we navigate in the `CLI COMMANDS` section, the "hamburger button" isn't present because the class css `folder-cli` is missing.
This PR add this class in order to show this button when we are in this section.
PR Close#28418
Show top menu at 992px screen width. The JS expression was checking just for screen widths
strictly greater than 992px to show the menu, while the CSS media query was showing the hamburger
icon just for screen widths strictly smaller than 992px, so there was a gap of 1px that the user
could't navigate through the top menu.
closes#24324
PR Close#26418
The `.properties-table` selector does not match any element and the
styles don't look relevant for the similarly named `.property-table`
class.
PR Close#28104
Filipe Silva
George Kalpakas
Roland Rytz
Brandon
Daniel Ruf
Igor Minar
Stephen Fluin
WilliamKoza
Jeremy Elbourn
Carlos Schneider