With the current way that the `HandTool` is implemented, if someone would try to also add a Zoom tool (as issue 1260 asks for) that probably wouldn't work very well given that you'd then have two cursor tools which may not play nice together.
Hence this patch, which attempts to refactor things so that it should be simpler to add e.g. a Zoom tool as well (given that that issue is marked as "good-beginner-bug", and I'm not sure if that really applies considering the current state of the code).
Note that I personally have no interest in implementing a Zoom tool (similar to Adobe Reader) since I wouldn't use it, but I figured that it can't hurt to make this code a bit more future proof.
Most of the files in this folder (except for the en-US folder and the
metadata.inc files) have been imported from the Firefox Aurora branch,
please see https://dxr.mozilla.org/l10n-mozilla-aurora/source/.
Some of the files are licensed under the MPL license. You can obtain a
copy of the license at https://mozilla.org/MPL/2.0.
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