layout: Lay absolutely-positioned blocks with inline containing blocks out of flow.
Removes the long space before the site-specific drop-down in the Google SERPs.
r? @glennw
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Have PaintLayers own StackingContexts instead of the opposite
Previously, StackingContexts might have a PaintLayer. We switch the
ownership, for several reasons:
* We want PaintLayers to potentially contain something other
than a StackingContext soon.
* We want to delay the creation of PaintLayers until the last
minute, so that we can synthesize new layers for sandwiched
content.
This commit also implements the second goal. Instead of creating
PaintLayers during layout itself, wait until we are sorting and
layerizing a completed DisplayList.
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Previously, StackingContexts might have a PaintLayer. We switch the
ownership, for several reasons:
* We want PaintLayers to potentially contain something other
than a StackingContext soon.
* We want to delay the creation of PaintLayers until the last
minute, so that we can synthesize new layers for sandwiched
content.
This commit also implements the second goal. Instead of creating
PaintLayers during layout itself, wait until we are sorting and
layerizing a completed DisplayList.
layout: Stop double-counting `position: relative` offsets for stacking contexts.
Fixes the location of the gear menu on the Google SERPs.
r? @mbrubeck
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Update prefs API to return an Option<bool>.
This allows for situations where there is no reasonable default
to apply for the pref value e.g. when we are just listing values
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margins.
* The code that attempted to strip out borders that span multiple
fragments in the same element could go wrong if fragments were
stripped out due to text clumping or whitespace stripping. This patch
rewrites that code to maintain flags in the inline fragment context
specifying whether the node is the beginning or end of the element.
Not only is this easier to maintain, it's closer in spirit to what roc
originally suggested two years ago: it's isomorphic to "begin element,
end element" markers for inline layout.
* Padding and margins for spans containing inline-blocks are now
properly handled via a division of labor between the `InlineBlock`
fragment and the `BlockFlow` that represents the inline-block.
* Unscanned text fragments may not be joined together into a text run if
borders, padding, or margins separate them.
Because Servo now matches the rendering of Gecko and WebKit on the
`input_button_margins_a` reftest, I had to modify it to add some
vertical alignment.
The combined effect of all of these fixes places "Advertising" on the
right place on google.com.
