Merge 143541

Merge 143541
> Account for transform in SVG background images
> https://bugs.webkit.org/show_bug.cgi?id=110295
> 
> Reviewed by Dirk Schulze.
> 
> Source/WebCore:
> 
> Tiled SVG background images are rendererd by drawing the SVG content into a temporary
> image buffer, then stamping out a tiled pattern using this buffer. Previously the
> image buffer did not account for CSS transforms which could result in pixelated backgrounds.
> 
> This patch takes advantage of the context's transform when sizing the temporary tiling
> image buffer. Because the context's transform also includes scale, this patch simplifies
> the SVG image code to no longer track scale.
> 
> Test: svg/as-background-image/svg-transformed-background.html
> 
> * loader/cache/CachedImage.cpp:
> (WebCore):
> (WebCore::CachedImage::imageForRenderer):
> 
>     CachedImage::lookupOrCreateImageForRenderer no longer creates images so it has been
>     refactored into just "imageForRenderer". Previously there were two versions of
>     lookupOrCreateImageForRenderer; these have been folded into imageForRenderer.
> 
> * loader/cache/CachedImage.h:
> * svg/graphics/SVGImage.cpp:
> (WebCore::SVGImage::drawPatternForContainer):
> 
>     To create the temporary tiling image buffer, the final size in screen coordinates is
>     needed. This is now computed using the current context's CTM. Because the CTM
>     already includes the page scale, all page scale tracking can be removed.
> 
>     The adjustments to srcRect and the pattern transform are the same as before, just
>     refactored to use imageBufferScale which has x and y components.
> 
> * svg/graphics/SVGImage.h:
> * svg/graphics/SVGImageCache.cpp:
> (WebCore::SVGImageCache::setContainerSizeForRenderer):
> 
>     Because the page scale needed to be cached between calls to
>     setContainerSizeForRenderer, this function was written to modify an existing cache
>     entry. Because the page scale no longer needs to be tracked, this code has been
>     simplified to re-write any existing cache entry.
> 
> (WebCore::SVGImageCache::imageSizeForRenderer):
> 
>     This function has been simplified by calling SVGImageForContainer::size() instead
>     of computing this value manually. The value returned remains the same, containing
>     the container size multiplied by zoom.
> 
> (WebCore::SVGImageCache::imageForRenderer):
> 
>     Previously we set the page scale on every call to imageForRenderer. Because page scale
>     no longer needs to be tracked, this function has been simplified to simply return
>     the cached SVGImageForContainer.
> 
> * svg/graphics/SVGImageForContainer.cpp:
> (WebCore::SVGImageForContainer::drawPattern):
> * svg/graphics/SVGImageForContainer.h:
> (WebCore::SVGImageForContainer::create):
> (WebCore::SVGImageForContainer::SVGImageForContainer):
> (SVGImageForContainer):
> 
> LayoutTests:
> 
> * svg/as-background-image/svg-transformed-background-expected.html: Added.
> * svg/as-background-image/svg-transformed-background.html: Added.
> 

TBR=pdr@google.com
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=144239

[pdr., 2013-02-27 22:22:20]

Committed patchset #1 manually as r144239.