Steps to reproduce a bug:
1. Open the attached project (TestShadow.zip)
2. Open the test.unity scene.
3. Enter the play mode of the game.
4. Open the Frame Debugger window.
5. Enable Frame Debugging.
6. Observe that the Depth Texture is renderred.

Expected results: The Depth Texture is not renderred because the Screen space shadows are disabled in the Graphics menu.
Actual results: The Depth Texture is renderred regardless.

Reproduced with: 5.4.1f1, 5.5.0b8 versions.
Not reproduced on the older version than 5.4, because Screen space shadows firstly appeared only on this version of Unity.

Note:
The depth renderring disappears if you set the shadows of the directional light to No Shadows, but the user needs them to be enabled.