"Your icon does not fill the entire icon space"

Google Play rejects many apps targeting TV with this infamous claim.

The entire rejection notice is as follows:

Issue found: No full-size app banner and/or icon

Your app should contain a full-size app banner and icon that is visible in the launcher. We are targeting 1080P, which we consider xhdpi. Apps should include the banner in the xhdpi (320 dpi) drawables folder with a size of (320px × 180px) and the icon with a size of (512px x512px). Please refer to our Home screen banner.

The title should help users identify apps in the launcher. Please refer to our Visual design and user interaction documentation for more information.

• Your icon does not fill the entire icon space.

Issue details

We found an issue in the following area(s):

• Version code 1987: In-app experience

About the Android TV App Quality Guidelines

We do not accept apps into Android TV that don't adhere to Android TV App Quality Guidelines.

Many app developers scratch their heads cluelessly. They desperately try all kinds of things to address this. This error may mean many things, so there may be many correct solutions. One of the them (not from me) can be illustrated as follows.

Suppose this is the launcher icon:

Google would allege the launcher icon on TV looks like this (I cannot reproduce this). You can see the two bottom corners of the triangle are cropped. 

The solution is to make the triangle smaller:

The round launcher icon will look like the following and satisfy Google: