Sync: Implement exponential re-sends

[AlexeyBarabash]

Description

Currently re-sends

Steps to Reproduce

1. Setup sync between deviceA and deviceB
2. ensure bookmarks are synced in derections A=>B and B=>A
   on deviceA:
3. open brave://inspect/#extensions
4. open inspect for Brave Sync
5. Enable timestamps settings (F1=>Console=>Show timestamps)
6. paste to the console

callbackList["send-sync-records"] = function(arg1, arg2, arg3) {
console.log(`TEST IGNORE send-sync-records ${arg2}`);
}

this will prevent send records to AWS
7. Create bookmark AA3.com on device A
8. Watch for TEST IGNORE send-sync-records in console
9. Expected to see in 10 minutes, then in 20 minutes ans so on.

Actual result:

8. Actual result: resend happens with interval of 60 minutes (or 10 minutes)

Expected result:

9. Expected: Resend happens with increasing intervals of 10,20,40,80,80,... minutes

Reproduces how often:

Easily

Brave version (brave://version info)

Brave	0.69.89 Chromium: 76.0.3809.62 (Developer Build) (64-bit)
Revision	7b77856b3aa34d72f246d12340fc1ded8b2c0e83-refs/branch-heads/3809@{#798}
OS	Linux

Version/Channel Information:

• Can you reproduce this issue with the current release?
• Can you reproduce this issue with the beta channel?
• Can you reproduce this issue with the dev channel?
• Can you reproduce this issue with the nightly channel?
  yes, for all

Other Additional Information:

• Does the issue resolve itself when disabling Brave Shields?
• Does the issue resolve itself when disabling Brave Rewards?
• Is the issue reproducible on the latest version of Chrome?

Miscellaneous Information:

[AlexeyBarabash]

Verified it works on Nightly (0.70.34).
The initially specified STR are not correct, because send records happens after successfull resolve and when network connection is turned off then send never happens.
Updates STR.

[AlexeyBarabash]

@GeetaSarvadnya @kjozwiak @srirambv @rebron - should the fix for this issue be uplifted to beta/dev/stable?

[btlechowski]

Verification passed on

Brave	0.69.130 Chromium: 77.0.3865.90 (Official Build) (64-bit)
Revision	58c425ba843df2918d9d4b409331972646c393dd-refs/branch-heads/3865@{#830}
OS	Ubuntu 18.04 LTS

Verified test plan from the description.

Verification passed on

Brave	0.69.130 Chromium: 77.0.3865.90 (Official Build) (64-bit)
Revision	58c425ba843df2918d9d4b409331972646c393dd-refs/branch-heads/3865@{#830}
OS	Windows 10 OS Version 1803 (Build 17134.1006)

• Verified test plan from the description.
  

Verified passed with

Brave	0.69.131 Chromium: 77.0.3865.90 (Official Build) (64-bit)
Revision	58c425ba843df2918d9d4b409331972646c393dd-refs/branch-heads/3865@{#830}
OS	macOS Version 10.13.6 (Build 17G5019)

• Verified STR from description