It appears that this whole time all IE8 unit tests ran only with jqLite. Due to a weird bug in IE[1], we never overwrote jqLite implementation with jQuery, so the tests ran with our jqLite instead.
This affected only IE8 (and likely older) and only in unit testing mode. angular.js - the built artifact binds to jQuery just find.
[1] https://plus.google.com/104744871076396904202/posts/Kqjuj6RSbbT
the flag must be in all src and test files so that we get the benefit of
running in the strict mode even in jstd
the following script was used to modify all files:
for file in `find src test -name "*.js"`; do
echo -e "'use strict';\n" > temp.txt
cat $file >> temp.txt
mv temp.txt $file
done
