Remove obsolete code from shortcut handler

These lines were introduced in 612f59aa10eef2bf6559deddfb54b84a0a30c6bc
when the only shortcuts were +/-/=/0 (to change zoom level).
Back then, when the input fields were focused, using these keys would
add these unwanted characters to the input field and change the zoom
level of the viewer. Having both operations at the same time was an
undesired event, so a check was inserted, to ignore shortcuts when
the toolbar is focused.

The #toolbar element doesn't exist any more, so these lines are obsolete.
[CRX] Pass expected length of stream to viewer

To get a progress bar for POST/FTP requests in Chromium.
Handle navigation keys when viewer is not focused

Restrict the scrollbar hack to the keycode for "spacebar",
since the bug only occurs in Firefox with spacebar.

Keyboard navigation is only activated for the spacebar if
the currently focused element is not a button.
Removes -moz-box-sizing usage
Fix wrong page being displayed when entering/exiting Presentation mode with zoom set to 'page-fit'
[B2G] Remove the spinner from the pageNumber field
Clean up toolbar images and add Retina assets.
Move print icons now that all icons are the same size
Fixed examples/acroforms/forms.js
Merge pull request #4319 from dferer/forms.js

Fixed examples/acroforms/forms.js
Trying to fix #4166
Merge pull request #4322 from prometheansacrifice/FixUnhandledExistingPageBug

Attempting to fix #4166
Faster JPX decoding
Merge pull request #4264 from fkaelberer/FasterJPXdecoding

Faster JPX decoding
Merge pull request #4315 from shorlander/master

Clean up toolbar images and add Retina assets.
Merge pull request #4327 from Snuffleupagus/issue-4315-followup

Move print icons now that all icons are the same size
Merge pull request #4262 from yurydelendik/issue4257

Removes -moz-box-sizing usage
Merge pull request #4328 from Snuffleupagus/b2g-remove-pageNumber-spinner

[B2G] Remove the spinner from the pageNumber field
Rewritten reftest analyzer from XHTML to HTML5
Merge pull request #4321 from timvandermeij/html5-analyzer

Rewritten reftest analyzer from XHTML to HTML5