Fix leaking of AddToHomescreenManager for WebAPKs.

Fix leaking of AddToHomescreenManager for WebAPKs.

Currently, AddToHomescreenManager is never destroyed when installing a WebAPK.
In this CL, we add a JNI call in the native side to destroy
AddToHomescreenManager after creating an install infobar for WebAPKs.

BUG=688444
Review-Url: https://codereview.chromium.org/2738823008
Cr-Commit-Position: refs/heads/master@{#455594}
(cherry picked from commit aefa25eb71bb437576f9b0f1b093b9909a211f62)

Review-Url: https://codereview.chromium.org/2744273002 .
Cr-Commit-Position: refs/branch-heads/3029@{#145}
Cr-Branched-From: 939b32ee5ba05c396eef3fd992822fcca9a2e262-refs/heads/master@{#454471}
Committed: https://chromium.googlesource.com/chromium/src/+/200438fbc2dde571fc36dce8cf6bf9baa8b1bcf2

[Xi Han, 2017-03-13 13:54:12]

Description was changed from

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Fix leaking of AddToHomescreenManager for WebAPKs.

Currently, AddToHomescreenManager is never destroyed when installing a WebAPK.
In this CL, we add a JNI call in the native side to destroy
AddToHomescreenManager after creating an install infobar for WebAPKs.

BUG=688444

Review-Url: https://codereview.chromium.org/2738823008
Cr-Commit-Position: refs/heads/master@{#455594}
(cherry picked from commit aefa25eb71bb437576f9b0f1b093b9909a211f62)
==========

to

==========
Fix leaking of AddToHomescreenManager for WebAPKs.

Currently, AddToHomescreenManager is never destroyed when installing a WebAPK.
In this CL, we add a JNI call in the native side to destroy
AddToHomescreenManager after creating an install infobar for WebAPKs.

BUG=688444

Review-Url: https://codereview.chromium.org/2738823008
Cr-Commit-Position: refs/heads/master@{#455594}
(cherry picked from commit aefa25eb71bb437576f9b0f1b093b9909a211f62)

Review-Url: https://codereview.chromium.org/2744273002 .
Cr-Commit-Position: refs/branch-heads/3029@{#145}
Cr-Branched-From:
939b32ee5ba05c396eef3fd992822fcca9a2e262-refs/heads/master@{#454471}
Committed:
https://chromium.googlesource.com/chromium/src/+/200438fbc2dde571fc36dce8cf6b...
==========

[Xi Han, 2017-03-13 13:54:14]

Committed patchset #1 (id:1) manually as
200438fbc2dde571fc36dce8cf6bf9baa8b1bcf2.