issue #5056. move gui test from ExtensionsTest to the outside
sounds pause automatically when switching background
issue #5056. fix linux & android compile error
closed #5054:Label:Text have black border if it's created with system font on WP8/WINRT.
closed #5056. fix  windows compile error
rename variable
Merge pull request #6628 from andyque/refactor5056

refactor 5056. pull gui tests from ExtensionTest to UITest
Merge pull request #6626 from Ryeeeeee/v3_pause_sound_background

sounds pause automatically when switching background
[ci skip]
Merge pull request #6631 from Dhilan007/v3_labelhotfixed

closed #5054:Label:Text have black border if it's created with system font on WP8/WINRT.
[ci skip]