there was a time (Android 1.x to around 2.x) where they were trying to cater to iOS users or at least attempting to get them to switch. some of the status bars of the time tried to mimic iOS's notification area as well. it is understandable they'd make a copy of the old Sad Mac icon (they also did this in Chrome, aka the 'Sad Tab'). as far as i know it's part of the bootloader. if the boot.img cannot find or cannot successfully complete the startup of an Android device for whatever reason (corrupted rooting, bad hack via root app, removing the wrong APK file like Android System, etc) the Dead Droid will display. from experience there are two different colors to the triangle which appears, one for recoverable (simply bad boot, booting with low battery, plugged in the wrong charger causing a random reboot and subsequent dump to the dead droid screen, etc) and another for unrecoverable. the red = bad. a factory reset is all that fixes it.
Now sometimes dead droid appears while recovery is factory resetting in the background and a simple power off and then back on will initiate a normal boot. normal recovery should look more like this:
Android screen of death:
Apple screen of death (classic):
Google Chrome:
Android Ice Cream Sandwich's additional screen of death mostly due to filesystem problems: