Bug 893310 - hdpi/xhdpi replacing @1.5x images assets for Gallery app
Merge pull request #10957 from cctuan/master-gallery

Bug 893310 - hdpi/xhdpi replacing @1.5x images assets for Gallery app, r=timdream
Patch for 889207

The message received before 12:00(AM) midnight is shown as TODAY
in thread_list

This patch triggers updateTimeHeaders on the next minute boundary,
instead of a 50 second poll.