Revert 239921 "Revert 239759 "The comment in base64.h implies th..."

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Reverting the revert. Congrats, the original CL wasn't the cause for the failure; sorry for the mess.
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> Revert 239759 "The comment in base64.h implies that base::Base64..."
> 
> > The comment in base64.h implies that base::Base64Encode() can return false, but
> > this cannot happen in practice. Fix the comment.
> > 
> > The implementation of Base64Encode() attempts to check for the return value
> > MODP_B64_ERROR as a failure, but modp_b64_encode() cannot return this
> > value. Remove the check.
> > 
> > Remove unneeded integer cast.
> > 
> > Change the return type to void.
> > 
> > BUG=323357
> > TEST=base_unittests, compile all
> > TBR=jochen@chromium.org,miket@chromium.org,joi@chromium.org,akalin@chromium.org,sergeyu@chromium.org
> > 
> > Review URL: https://codereview.chromium.org/86913002
> 
> TBR=ricea@chromium.org
> 
> Review URL: https://codereview.chromium.org/101113004

TBR=vadimt@chromium.org

Review URL: https://codereview.chromium.org/111883004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@239944 0039d316-1c4b-4281-b951-d872f2087c98
Add diagnostic logs for transparent app icons for component extension

Transparent icon is hard to repo. I haven't repo it. Adding some log
message to help diagonsis.


BUG=314872

Review URL: https://codereview.chromium.org/102033005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@239945 0039d316-1c4b-4281-b951-d872f2087c98
Add x-chrome-connnected:focus_id header to drive

For background please refer to the design doc https://docs.google.com/a/google.com/document/d/1KTTS3fOddY2nxq8scd05SpNFP3I4WsgfQzD0nnZm2zg/edit#heading=h.tfzj12peb2h

BUG=293733

Review URL: https://codereview.chromium.org/102183002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@239946 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 239945
Fix the crash when closing multiple tabs with gaia auth extension

BUG=315366, 313281

Review URL: https://codereview.chromium.org/105383003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@239947 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 239947
Revert 239923 "Revert 239771 "SyncFS v2: Add re-initialization c..."

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Reverting the revert. Congrats, the original CL wasn't the cause for the failure; sorry for the mess.
*****************

> Revert 239771 "SyncFS v2: Add re-initialization code for tempora..."
> 
> Lightly suspected of causing failures on CrOS:
> 
> http://build.chromium.org/p/chromium.chromiumos/builders/Linux%20ChromiumOS%20Tests%20%28dbg%29%282%29/builds/9981
> 
> > SyncFS v2: Add re-initialization code for temporary service failure case
> > 
> > Also run SyncEngineInitializer task at high priority.
> > 
> > BUG=240165
> > TEST=manual
> > 
> > Review URL: https://codereview.chromium.org/110113003
> 
> TBR=kinuko@chromium.org
> 
> Review URL: https://codereview.chromium.org/111893007

TBR=scottmg@chromium.org

Review URL: https://codereview.chromium.org/108263004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@239948 0039d316-1c4b-4281-b951-d872f2087c98
Disable PolicyPathParserTests.AllPlatformVariables on Mac since it's flaky 10% of the time on trybots.

BUG=327520
TBR=pastarmovj@chromium.org

Review URL: https://codereview.chromium.org/111893009

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@239949 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 239949