https://bugs.webkit.org/show_bug.cgi?id=60421

Custom scrollbars nested inside an overlay scrollbar overflow region end up painting twice -and corresponding- <rdar://problem/9389072> Reviewed by Darin Adler. Source/WebCore: Be sure not to paint custom css scrollbars during the special overlay-scrollbar painting pass. * rendering/RenderLayer.cpp: (WebCore::RenderLayer::paintOverflowControls): LayoutTests: * platform/mac/scrollbars/scrollbars-on-positioned-content-expected.png: Added. * platform/mac/scrollbars/scrollbars-on-positioned-content-expected.txt: Added. * scrollbars/scrollbars-on-positioned-content.html: Added. git-svn-id: http://svn.webkit.org/repository/webkit/trunk@85990 268f45cc-cd09-0410-ab3c-d52691b4dbfc

https://bugs.webkit.org/show_bug.cgi?id=60421
Custom scrollbars nested inside an overlay scrollbar overflow region end up painting twice -and corresponding- <rdar://problem/9389072> Reviewed by Darin Adler. Source/WebCore: Be sure not to paint custom css scrollbars during the special overlay-scrollbar painting pass. * rendering/RenderLayer.cpp: (WebCore::RenderLayer::paintOverflowControls): LayoutTests: * platform/mac/scrollbars/scrollbars-on-positioned-content-expected.png: Added. * platform/mac/scrollbars/scrollbars-on-positioned-content-expected.txt: Added. * scrollbars/scrollbars-on-positioned-content.html: Added. git-svn-id: http://svn.webkit.org/repository/webkit/trunk@85990 268f45cc-cd09-0410-ab3c-d52691b4dbfc
a74aad02 · bdakin@apple.com · 090c78dd · a74aad02 · a74aad02 · a74aad02
Commit a74aad02 authored May 07, 2011 by bdakin@apple.com
6 changed files
--- a/LayoutTests/ChangeLog
+++ b/LayoutTests/ChangeLog
+2011-05-06  Beth Dakin  <bdakin@apple.com>
+
+        Reviewed by Darin Adler.
+
+        https://bugs.webkit.org/show_bug.cgi?id=60421
+        Custom scrollbars nested inside an overlay scrollbar overflow region end up 
+        painting twice
+        -and corresponding-
+        <rdar://problem/9389072>
+
+        * platform/mac/scrollbars/scrollbars-on-positioned-content-expected.png: Added.
+        * platform/mac/scrollbars/scrollbars-on-positioned-content-expected.txt: Added.
+        * scrollbars/scrollbars-on-positioned-content.html: Added.
+
 2011-05-06  Abhishek Arya  <inferno@chromium.org>

        Unreviewed.
--- a/LayoutTests/platform/mac/scrollbars/scrollbars-on-positioned-content-expected.png
+++ b/LayoutTests/platform/mac/scrollbars/scrollbars-on-positioned-content-expected.png
--- a/LayoutTests/platform/mac/scrollbars/scrollbars-on-positioned-content-expected.txt
+++ b/LayoutTests/platform/mac/scrollbars/scrollbars-on-positioned-content-expected.txt
+layer at (0,0) size 800x600
+  RenderView at (0,0) size 800x600
+layer at (0,0) size 800x600
+  RenderBlock {HTML} at (0,0) size 800x600
+    RenderBody {BODY} at (8,8) size 784x576
+      RenderBlock {P} at (0,0) size 784x18
+        RenderText {#text} at (0,0) size 657x18
+          text run at (0,0) width 657: "This test passes if the custom scrollbar paints in the corrext spot, which is at the bottom of the purple div."
+layer at (8,50) size 304x550 clip at (9,51) size 287x533 scrollWidth 302 scrollHeight 1311
+  RenderBlock (positioned) {DIV} at (8,50) size 304x550 [border: (1px solid #FF0000)]
+    RenderBlock {DIV} at (1,412) size 15x900 [bgcolor=#008000]
+layer at (9,51) size 302x411 backgroundClip at (9,51) size 287x411 clip at (10,52) size 286x400 outlineClip at (9,51) size 287x533 scrollWidth 500
+  RenderBlock {DIV} at (1,1) size 302x411 [border: (1px solid #0000FF)]
+    RenderBlock {DIV} at (1,1) size 500x400 [bgcolor=#800080]
--- a/LayoutTests/scrollbars/scrollbars-on-positioned-content.html
+++ b/LayoutTests/scrollbars/scrollbars-on-positioned-content.html
+<html>
+	<head>
+		<style type="text/css">
+		.tables
+		{
+			border: 1px solid red;
+			overflow-y: auto;
+			top: 50px;
+			bottom: 0px;
+			position: absolute;
+		}
+		
+		.wrapper
+		{
+			border: 1px solid blue;
+			overflow-x: auto;
+			width: 300px;
+		}
+
+		.wrapper::-webkit-scrollbar
+		{
+			height: 9px;
+		}
+
+		.wrapper::-webkit-scrollbar-track
+		{
+			background-color: #E3E3E3;
+		}
+
+		.wrapper::-webkit-scrollbar-thumb
+		{
+			background: #CCCCCC;
+			border: 1px solid #ADADAD;
+		}
+		</style>
+	</head>
+	
+	<body>
+		
+		<p>This test passes if the custom scrollbar paints in the corrext spot, which is at the bottom of the purple div.</p>
+
+		<div class="tables">
+		<div class="wrapper">
+	
+			<div style="background-color:purple; width:500px; height:400px;"></div>
+
+		</div>
+		
+        <div style="background-color:green; width:15px; height:900px;"></div>
+        
+        </div>
+        
+	</body>
+</html>
--- a/Source/WebCore/ChangeLog
+++ b/Source/WebCore/ChangeLog
+2011-05-06  Beth Dakin  <bdakin@apple.com>
+
+        Reviewed by Darin Adler.
+
+        https://bugs.webkit.org/show_bug.cgi?id=60421
+        Custom scrollbars nested inside an overlay scrollbar overflow region end up 
+        painting twice
+        -and corresponding-
+        <rdar://problem/9389072>
+
+        Be sure not to paint custom css scrollbars during the special overlay-scrollbar 
+        painting pass.
+        * rendering/RenderLayer.cpp:
+        (WebCore::RenderLayer::paintOverflowControls):
+
 2011-05-06  Cary Clark  <caryclark@google.com>

        Reviewed by Eric Seidel.
--- a/Source/WebCore/rendering/RenderLayer.cpp
+++ b/Source/WebCore/rendering/RenderLayer.cpp
@@ -2251,6 +2251,10 @@ void RenderLayer::paintOverflowControls(GraphicsContext* context, int tx, int ty
        return;
    }

+    // This check is required to avoid painting custom CSS scrollbars twice.
+    if (paintingOverlayControls && !hasOverlayScrollbars())
+        return;
+
    int offsetX = tx;
    int offsetY = ty;
    if (paintingOverlayControls) {