Import local files to ipfs

[spylogsster]

Description

Add IPFS submenu to the main app menu and add an item to import local file to ipfs.
Copy sharable link if import successful

Expected result:

File accessable by public gateway sharable link

[lidel]

• Shareable link should use Gateway selected by user or dweb.link if no choice was made.
• If a single file was imported, copy direct link that looks like this: https://dweb.link/ipfs/{fileCid}?filename={filename}
• If you want to support import of multiple files at the same time, then you copy the CID of the root directory https://dweb.link/ipfs/{dirCid}
• Prewarm shared gateway link
  • Initial load of shared link may take time (gateway needs to find content first, and fetch it), so sending asynchronous HTTP HEAD to the gateway speeds things up (eg. https://dweb.link/ipfs/{cid})
  • It is acceptable because it only triggers content lookup that would happen anyway after other person opens shared link, and no privacy is decreased, because gateway will find the IP of original provider anyway.

[rebron]

cc: @karenkliu

[stephendonner]

Verified PASSED using brave/brave-core#8423 with build

Brave	1.25.28 Chromium: 90.0.4430.72 (Official Build) nightly (x86_64)
Revision	b6172ef8d07ef486489a4b11b66b2eaeed50d132-refs/branch-heads/4430@{#1233}
OS	macOS Version 11.2.3 (Build 20D91)

Steps:

1. loaded ipns://en.wikipedia-on-ipfs.org
2. clicked on Use a local node
3. waited until installation and configuration finished
4. loaded https://archive.org/details/spellbound1945_202001
5. context-clicked on the MPEG4 link and chose Save link as...
6. saved Spellbound (1945, USA) Director Alfred Hitchcock Starring Ingrid Bergman, Gregory Peck - Film Noir.mp4 to desktop
7. clicked the hamburger menu, chose top-level IPFS > Share Local File using IPFS
8. chose Spellbound (1945, USA) Director Alfred Hitchcock Starring Ingrid Bergman, Gregory Peck - Film Noir.mp4
9. waited
10. once I got the system notification for the shared IPFS-content link, I pasted it from clipboard into Slack
11. on my Windows 10 machine, using nightly, clicked on the https://dweb.link/ipfs/QmfRpQsfixeYHbJF2vqQH4ZBJ8DWmVTXX8oKpoYGZLT2qJ?filename=Spellbound+(1945%2C+USA)+Director+Alfred+Hitchcock+Starring+Ingrid+Bergman%2C+Gregory+Peck+-+Film+Noir.mp4 link and waited
12. it took around 10 minutes (as @spylogsster said) for the link to resolve and then it quickly downloaded and started playing on my Windows 10 machine

example	example	example	example

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Verification passed on

Brave	1.25.59 Chromium: 90.0.4430.212 (Official Build) beta (64-bit)
Revision	e3cd97fc771b893b7fd1879196d1215b622c2bed-refs/branch-heads/4430@{#1429}
OS	Ubuntu 18.04 LTS

Verified test plan from brave/brave-core#8423

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Verification passed on

Brave | 1.25.57 Chromium: 90.0.4430.93 (Official Build) beta (64-bit)
-- | --
Revision | 4df112c29cfe9a2c69b14195c0275faed4e997a7-refs/branch-heads/4430@{#1348}
OS | Windows 10 OS Version 2004 (Build 19041.985)

• Verified the steps from above test plan mentioned by @stephendonner
• Logged IPFS sub menu is not shown in the main app menu until browser is restarted #15822

example	example	example