Steps to reproduce
1. Create a new project.
2. In the Hierarchy window, create a Text gameObject.
3. Select Text object.
4. In the Inspector, click on the Anchor Presets button.
5. Press Shift or Alt

Expected result: new preset images appear, representing "Also set pivot" and "Also set position" options
Actual result: No new preset images appear, input is leaked to the editor
Note: Functionality from pressing Shift persists. Functionality from pressing alt disappears (window gets dragged when holding alt button)

Reproduced on: 5.6.3f1, 2017.1.1f1, 2017.2.0f3, 2017.3.0b1

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FIXED IN 2017.3.0f1