form-field(outline): placeholder animation with matPrefix icon not moving to the top left border

What is the expected behavior?
When clicking on the input, The placeholder should move to the top left side of the border.

https://material.io/design/components/text-fields.html
In the link above, Choose OUTLINED and check the following options : 'Leading icon' and 'Trailing icon'
Click on the placeholder and it will move to the top left side correctly,

What is the current behavior?
Currently when there is a matPrefix mat-icon and the appearance is 'outline', When clicking on the input field, The placeholder goes to the top of the field but not to the left (probably because of the icon).

What are the steps to reproduce?
https://stackblitz.com/angular/ygjnerlpdko?file=src%2Fapp%2Fform-field-appearance-example.html

On the html file, Change the 3rd input from matSuffix to matPrefix and click on the placeholder

Which versions of Angular, Material, OS, TypeScript, browsers are affected?
I'm on Chrome 78.0.3904.108 , Windows10, AngularCLI 8.3.3, Material 8.2.3

Is there anything else we should know?

リンクされた StackBlitz の再現例と、そのエントリーポイントである src/app/form-field-appearance-example.html から開始します。3 番目の入力を matSuffix から matPrefix に変更し、outline appearance にして、placeholder の移動を再現します。プレフィックスアイコンに対する Angular Material form-field の outline の動作を追跡します。フォーカス中の placeholder が左上の境界線まで移動し、matPrefix アイコンが正しく配置されたままになれば完了です。

索引モデルが issue の本文から書いたものです。