Add support to provide app its own ANR stack trace

...If it was killed due to ANR.

Also add support to set a cookie which could be
included into the app kill reason.

Bug: 148413462
Test: atest CtsAppExitTestCases:ActivityManagerAppExitInfoTest
Change-Id: Ia5385834e804f1cff33b53702ddb2d36f86950a4