[SCM] WebKit Debian packaging branch, webkit-1.2, updated. upstream/1.1.90-6072-g9a69373

[eric at webkit.org]

The following commit has been merged in the webkit-1.2 branch:
commit ed5f2c248fe9657cf20561d8420ff703a6d8926d
Author: eric at webkit.org <eric at webkit.org@268f45cc-cd09-0410-ab3c-d52691b4dbfc>
Date:   Sat Dec 19 06:40:22 2009 +0000

    2009-12-18  Peter Kasting  <pkasting at google.com>
    
            Reviewed by Simon Fraser.
    
            Add a comment about some confusing code that otherwise would look like
            it might be a bug.
            https://bugs.webkit.org/show_bug.cgi?id=32534
    
            * rendering/RenderLayer.cpp:
            (WebCore::RenderLayer::updateScrollInfoAfterLayout):
    
    git-svn-id: http://svn.webkit.org/repository/webkit/trunk@52379 268f45cc-cd09-0410-ab3c-d52691b4dbfc

diff --git a/WebCore/ChangeLog b/WebCore/ChangeLog
index c28c69e..c4ace02 100644
--- a/WebCore/ChangeLog
+++ b/WebCore/ChangeLog
@@ -1,3 +1,14 @@
+2009-12-18  Peter Kasting  <pkasting at google.com>
+
+        Reviewed by Simon Fraser.
+
+        Add a comment about some confusing code that otherwise would look like
+        it might be a bug.
+        https://bugs.webkit.org/show_bug.cgi?id=32534
+
+        * rendering/RenderLayer.cpp:
+        (WebCore::RenderLayer::updateScrollInfoAfterLayout):
+
 2009-12-18  Nikolas Zimmermann  <nzimmermann at rim.com>
 
         Not reviewed. Messed up the XCode file, trying to fix.
diff --git a/WebCore/rendering/RenderLayer.cpp b/WebCore/rendering/RenderLayer.cpp
index 4b7d635..922a90a 100644
--- a/WebCore/rendering/RenderLayer.cpp
+++ b/WebCore/rendering/RenderLayer.cpp
@@ -1890,6 +1890,14 @@ RenderLayer::updateScrollInfoAfterLayout()
         if (pageStep < 0) pageStep = clientWidth;
         m_hBar->setSteps(cScrollbarPixelsPerLineStep, pageStep);
         m_hBar->setProportion(clientWidth, m_scrollWidth);
+        // Explicitly set the horizontal scroll value.  This ensures that when a
+        // right-to-left scrollable area's width (or content width) changes, the
+        // top right corner of the content doesn't shift with respect to the top
+        // right corner of the area. Conceptually, right-to-left areas have
+        // their origin at the top-right, but RenderLayer is top-left oriented,
+        // so this is needed to keep everything working (see how scrollXOffset()
+        // differs from scrollYOffset() to get an idea of why the horizontal and
+        // vertical scrollbars need to be treated differently).
         m_hBar->setValue(scrollXOffset());
     }
     if (m_vBar) {

-- 
WebKit Debian packaging