when click mat-select input focus another input

#### Reproduction

Hi guys. I use ionic 4 and integrated angular material into my projects. Everything work perfectly but when I want to create the custom select component with search input I seem this issue. When open mat-select and click search input application focused another input. I don't solve this problem. I don't know maybe it's a bug. I upload *.gif file for more detail.

#### My Codes

```

```

Custom **mat-select** component:
```

{{label | translate}}

#### Screen


#### My Packages
```

`"@angular/animations": "8.2.14",
"@angular/cdk": "8.2.3",
"@angular/common": "8.2.14",
"@angular/core": "8.2.14",
"@angular/forms": "8.2.14",
"@angular/material": "8.2.3",
"@angular/platform-browser": "8.2.14",
"@angular/platform-browser-dynamic": "8.2.14",
"@angular/router": "8.2.14",
"@ionic-native/core": "5.17.1",
"@ionic-native/file": "5.17.1",
"@ionic-native/file-opener": "5.17.1",
"@ionic-native/file-transfer": "5.17.1",
"@ionic-native/in-app-browser": "^5.18.0",
"@ionic-native/keyboard": "^5.19.0",
"@ionic-native/network": "^5.18.0",
"@ionic-native/onesignal": "^5.18.0",
"@ionic-native/splash-screen": "5.17.1",
"@ionic-native/status-bar": "5.17.1",
"@ionic/angular": "4.11.5",
"@ionic/storage": "^2.2.0",`

```

Comienza reproduciendo el comportamiento con la plantilla personalizada de mat-select y el marcado del formulario que se muestran en el issue, centrándote en el campo de búsqueda incrustado y en el otro campo de entrada del formulario. Rastrea la gestión del foco de mat-select durante la apertura y los clics en los campos de entrada; se considera terminado cuando el campo de búsqueda recibe el foco sin que este se desplace a otro campo de entrada, y la reproducción se haya verificado con las versiones de Angular Material indicadas.

Escrito por el modelo de indexación a partir del texto del issue.