[4.0.0-beta.15-0] Tab bar bottom safe area not expanding height

[sbannigan]

Bug Report

Ionic Info
Run ionic info from a terminal/cmd prompt and paste the output below.

Ionic:

   ionic (Ionic CLI)          : 4.1.1 (/usr/local/lib/node_modules/ionic)
   Ionic Framework            : @ionic/angular 4.0.0-beta.15-0
   @angular-devkit/core       : 0.7.5
   @angular-devkit/schematics : 0.7.2
   @angular/cli               : 6.1.2
   @ionic/ng-toolkit          : not installed
   @ionic/schematics-angular  : not installed

System:

   NodeJS : v8.11.2 (/usr/local/bin/node)
   npm    : 6.4.1
   OS     : macOS

Describe the Bug
Safe area padding on the bottom of the new ion-tab-bar does not display correctly. It adds the padding but the height of the bar does not change, shrinking the tab bar content instead:

Expected Behavior
Safe area padding should push the tab bar up instead of shrinking the content like so:

Additional Context
Was able to override this for now by using margin instead of padding:

ion-tab-bar.placement-bottom {
    padding-bottom: 0;
    margin-bottom: var(--ion-safe-area-bottom, 0px);
}

The original implementation used padding though, so I don't feel like that is a permanent fix.

[ionitron-bot]

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