Expose thumbnails of pages to iOS share extensions.

Expose thumbnails of pages to iOS share extensions.

This CLs implements UIActivityItemSource's
|activityViewController:thumbnailImageForActivityType:suggestedSize:|.
Also:
-factor out of the BVC the creation of ShareToData.
-remove unused UIActivityURLSource.
-fix ui/base/test/ios/OWNERS (broken by
https://codereview.chromium.org/1885043012 )

TEST=Share a page from Chrome iOS to the Chrome iOS extension. A
thumbnail of the page should be shown.
BUG=686049
Review-Url: https://codereview.chromium.org/2645653003
Cr-Commit-Position: refs/heads/master@{#447977}
(cherry picked from commit 4a8cf9449a9df503e1993433249a9e6923b5d810)

Review-Url: https://codereview.chromium.org/2682043002 .
Cr-Commit-Position: refs/branch-heads/2987@{#383}
Cr-Branched-From: ad51088c0e8776e8dcd963dbe752c4035ba6dab6-refs/heads/master@{#444943}
Committed: https://chromium.googlesource.com/chromium/src/+/a2186c11d838c7a5633197018ec3727360827623

[jif, 2017-02-08 09:47:02]

Description was changed from

==========
Expose thumbnails of pages to iOS share extensions.

This CLs implements UIActivityItemSource's
|activityViewController:thumbnailImageForActivityType:suggestedSize:|.
Also:
-factor out of the BVC the creation of ShareToData.
-remove unused UIActivityURLSource.
-fix ui/base/test/ios/OWNERS (broken by
https://codereview.chromium.org/1885043012 )

TEST=Share a page from Chrome iOS to the Chrome iOS extension. A
thumbnail of the page should be shown.
BUG=686049

Review-Url: https://codereview.chromium.org/2645653003
Cr-Commit-Position: refs/heads/master@{#447977}
(cherry picked from commit 4a8cf9449a9df503e1993433249a9e6923b5d810)
==========

to

==========
Expose thumbnails of pages to iOS share extensions.

This CLs implements UIActivityItemSource's
|activityViewController:thumbnailImageForActivityType:suggestedSize:|.
Also:
-factor out of the BVC the creation of ShareToData.
-remove unused UIActivityURLSource.
-fix ui/base/test/ios/OWNERS (broken by
https://codereview.chromium.org/1885043012 )

TEST=Share a page from Chrome iOS to the Chrome iOS extension. A
thumbnail of the page should be shown.
BUG=686049

Review-Url: https://codereview.chromium.org/2645653003
Cr-Commit-Position: refs/heads/master@{#447977}
(cherry picked from commit 4a8cf9449a9df503e1993433249a9e6923b5d810)

Review-Url: https://codereview.chromium.org/2682043002 .
Cr-Commit-Position: refs/branch-heads/2987@{#383}
Cr-Branched-From:
ad51088c0e8776e8dcd963dbe752c4035ba6dab6-refs/heads/master@{#444943}
Committed:
https://chromium.googlesource.com/chromium/src/+/a2186c11d838c7a5633197018ec3...
==========

[jif, 2017-02-08 09:47:04]

Committed patchset #1 (id:1) manually as
a2186c11d838c7a5633197018ec3727360827623.