Bumping gaia.json for 2 gaia-central revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/d5ebee6f3764
Author: Pavel Ivanov <pivanov@mozilla.com>
Desc: Merge pull request #13767 from pivanov/bug-939139

Bug 939139 - [Music] Update scrubber to be consistent with the video player

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https://hg.mozilla.org/integration/gaia-central/rev/88965740b73a
Author: Pavel Ivanov <pivanov@mozilla.com>
Desc: Bug 939139 - [Music] Update scrubber to be consistent with the video player
Bug 884706 - Update getDefaultScale. r=mwu
Bug 929973 - Implement android::IGraphicBufferAlloc in B2G. r=mwu, r=mikeh
Bug 939654 - Remove unnecessary wait from instantiating MediaResourceManagerService. r=mwu
Bumping gaia.json for 2 gaia-central revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/32c72fb8d857
Author: Ryan VanderMeulen <rvandermeulen@mozilla.com>
Desc: Merge pull request #13448 from mschwart/bug935780

Bug 935780 - Observe stk timeout settings

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https://hg.mozilla.org/integration/gaia-central/rev/f3743a61c002
Author: Michael Schwartz <mschwart@codeaurora.org>
Desc: Bug 935780 - Observe stk timeout settings r=frsela

Change-Id: Id467189e521d24aed34437e6916d06a5aea6ec6d
Merge b2g-inbound to m-c