The link to download extensions in addon dialog should be updated to a page we maintained for moblin image

[Zhao Fan]

Bug detailed description:
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We have patched a few extensions to make them work on midbrowser, so we need to maintain a page on moblin.org to host these extensions and we need to modify the link on the addon dialog correspondingly to point to the our page.

Reproduce steps:
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Current result:
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Expected result:
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Basic root-causing log:
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[Jimmy Huang (jimmyhuang-deactivatedaccount)]

Changing to fix-later, because add-on support is not in the POR.

[Alexander Sack (asac)]

this isnt an issue anymore as the addons dialog has changed considerably. The right solution would be to enable the midbrowser target application to be listed on addons.mozilla.org. Maybe it already works? if not, let me know; i can mediate if we want to have midbrowser enabled on that site.

[Jimmy Huang (jimmyhuang-deactivatedaccount)]

The problem of add-ons for midbrowser is not only just the target application ids, but some or i would say most of the add-ons needs some modification to the source code where they references the chrome urls to be midbrowser, which makes a lot of those add-ons don't work out of the box when installed in the midbrowser enviroment. That's why we rather not allow any add-ons to be retrieved through the addons portal instead of user downloading and installing an add-on, but then finds it non-functional.