In the tests environmnent, we don't want img and iframe nodes to
perform RPCs when they are inserted into the DOM. For img nodes,
we prefixed the src attribute by '#test: ' as soon as they were
inserted into the DOM. Unfortunately, this didn't work as expected:
an RPC was done to fetch route '/web/tests?' (i.e. the tests page),
because everything after '#' in the url isn't sent to the server.
This rev. completely removes the src attribute of img nodes, and
set a 'data-src' attribute with the original src attribute's value,
so that it can still be checked in the tests.
Tests using this attribute have been adapted accordingly.
Aaron Bohy
c265e47a63