material/form-field(outline): text is misaligned vertically when no mat-label defined

#### Reproduction

https://angular-input-outline.stackblitz.io

Steps to reproduce:
1. Type into the input


#### Expected Behavior

The text should be vertically aligned in the input box.

#### Actual Behavior

The text is misaligned vertically.

#### Environment

- Angular: 8.2.14
- CDK/Material: 8.2.3
- Browser(s): Chrome, Firefox
- Operating System (e.g. Windows, macOS, Ubuntu): Windows

Start with the linked StackBlitz reproduction and compare the outlined mat-form-field behavior when no mat-label is defined. Trace the Angular Material form-field implementation from the reproduction, then verify the result in Chrome and Firefox. Done means typed text is vertically aligned within the input box without a mat-label.

Written by the indexing model from the issue text.