Burger menu icon is misaligned in Gradient Editor of Trail Renderer.

Steps to repro:
1. Create a new project.
2. GameObject> Create Empty > Add Component > Trail Renderer.
3. Open color gradient editor window.

Actual Result:
Burger menu icon is misaligned in Gradient Editor

Expected Result:
Burger menu icon is aligned in Gradient Editor

Reproducible in:
2020.1.0a2, 2019.3.0b1, 2019.3.0a3.

Working Fine in:
2019.3.0a2, 2019.2.0f1.

Environment:
Windows & Mac 10.14.