Bug 960277. Part 1: Don't optimize away frame reconstruction for 'transform' add/remove if the element has complex abs-pos container structure. r=mats

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extra : rebase_source : 4a1b57df9146a31ce8e25a7b215d2eb1edb09a55
Bug 960277. Part 2: Move nsFieldSetFrame declaration to nsFieldSetFrame.h. r=mats

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extra : rebase_source : 6b0da46311f24238d48c6d8045fe87c6f90d11ce
Bug 960277. Part 3: nsFieldSetFrame's anonymous child should not inherit CSS 'position', but should still be an abs-pos containing block if the fieldset is. r=mats

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extra : rebase_source : 9e1109c3c1216df58281b7c81447e44da97f681b
Bug 647813. XUL popups anchored to a <select> should not size themselves to the <select>. r=mats

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extra : rebase_source : 3be93d1e796ef8ec4e6565a083e9abe19879566e