This reverts commit 75449088.

I need the test suite working to release 3.0~beta2, and it's been quite broken
on feature/stretch since the merge of test/12059-dogtail-optimizations.

refs: #12305

We have decided to remove I2P (Refs: #11276) due to our failure of
finding someone interested in maintaining it in Tails.

Will-fix: #12263

... to significantly improve Dogtail's performance by saving state and
reusing it between Dogtail commands.

This is a massive commit, and it changes the semantics of the creation
of Dogtail objects. Previously they just created the code that then
would be run once an actionable method was called (.wait, .click etc),
but now it works like in Python, that Dogtail will try to find the
graphical element upon object creation.

Will-fix: #12059

We previously relied on Sikuli, and the image was made outdated thanks
to our donation campaign. No more!

Will-fix: #11911

So we don't repeat the more verbose Dogtail instanciation every time.

Also, this is a great simplification. :)

It turns out the previous code had multiple errors (symbol error
because of True when it should be true, no .wait so the generated
python code was never run) but even after fixing them I learned that
try_for and assert_raise doesn't work together because it will catch
try_for's timeout exception. Even when telling assert_raise to look
for a specific exception it will still catch the other ones and then
interpret them as an assertion failure, so the try_for never
halts. Yay. It should be possible to get an ~assert_raise that we need
here with some begin-rescue logic, but let's not bother.

This step was broken due to Tor Browser 6.0.x changing the zoom-levels
(or similar) so various elements of the just removed image were not
positioned the way we expected them.

It doesn't make sense now when we use Chutney since that always means
it will report that Tor is not being used.

In some scenarios we used it simply because we needed *some* page
(distinct from the Tails News page) and we had the image. In those
cases we now use the Tails homepage instead. I tried to use dogtail,
but realized that dogtail won't work for the Unsafe Browser due to

In this case, a Tor Check failure is expected.

With this step implemented with Dogtail, we don't refer to camel cased
.png:s any more, but to the actual label, e.g. "Some application"
rather than "SomeApplication".

... where we have the Tor Browser. For consistency.

... instead of the crazy workaround we had to use before. It turns out
you *can* use -app and -profile together, but only if -profile is
given last. It may be that it was fixed recently, because I'm pretty
sure it didn't work last time I wroked on this.

Also, in /usr/share/TorBrowser/Data/Browser (which is the "default"
profile directory relative to the Tor Launcher applocation.ini file)
the Caches directory must exist and be accessible for the tor-launcher
user even if -profile is used, so we just have to ensure it exists.

Will-fix: #7943

We were waiting for the dialog (BrowserDownloadDialog.png) to show up, and then
clicking on a button that is part of that dialog
(BrowserDownloadDialogSaveAsButton.png). In the past we've seen such
implementations be fragile, due to race conditions between when all the widgets
in a window are drawn vs. when Sikuli notices the first ones appear.

So, let's consider that "I get the browser download dialog" really means "I get
the browser download dialog including all its widgets that we are really
interested in".

refs: #9285

Per the discussion on ticket #9285 we should exchange the scenario
that tries to open a downloaded file in an external application (which
we now do not allow) with a scenario where we just downloads a file.

Refs: #9285

Will-fix: #5330

When entering an address like"http(s)" we sometime end up with
"htp(s)", so either the second or third character is lost. My guess is
the second; once the first character is entered, the Tor Browser
immediately starts showing the list of suggestions, and it seems if
the second character is timed at some particular point when this list
is being shown, it's lost.

This is worked around by just pasting the whole address in one go, via
the clipboard.

Will-fix: #10467