[webkit-reviews] review requested: [Bug 27538] Qt memory consumption on site with many images : [Attachment 33252] Change the Qt image decoding to be closer to cairo

[bugzilla-daemon at webkit.org]

Holger Freyther <zecke at selfish.org> has asked  for review:
Bug 27538: Qt memory consumption on site with many images
https://bugs.webkit.org/show_bug.cgi?id=27538

Attachment 33252: Change the Qt image decoding to be closer to cairo
https://bugs.webkit.org/attachment.cgi?id=33252&action=review

------- Additional Comments from Holger Freyther <zecke at selfish.org>
Introduce an RGBA32Buffer buffer implementation for Qt. The
actualy buffer is a WTF::Vector (to use fastMalloc) but we
have a image on top of this we are using for manipulation,
width/heigt.

Re-Implement ImageDecoderQt on top of the ImageDecoder using
the RGBA32Buffer to hold the final image and attempt to delay
image decoding until the actual image data is requested. This
is failing for gif were we need to decode the images in frameCount()
due QImageReader limitations. Add a side-channel to RGBA32Buffer
because QImageReader can not decode to the QImage we give it.

Change the ImageSourceQt.cpp to be close cairo and change
ImageQt.cpp to free the native image pointer (QPixmap) now that
the ownership of QPixmap's is the same as in other ports.

This change makes the ownership of RGBA32Buffer and native
images/pixmaps follow other ports and allows to easily use
the WebCore image decoders.
---
 8 files changed, 414 insertions(+), 321 deletions(-)