From cfc8100176661524acd3c973ae3c33e138eaf7f5 Mon Sep 17 00:00:00 2001
From: Stuart Morgan <stuart.morgan+bugzilla@gmail.com>
Date: Fri, 6 Nov 2009 11:17:45 +0100
Subject: [PATCH] Bug 425958 - Fill an opaque NSView with white when Gecko
 refuses to draw, because not drawing anything means that garbage reaches the
 screen. r=mstange

--HG--
extra : rebase_source : c43ccac7359cd376a4f6a138f538d203dc281909
---
 widget/src/cocoa/nsChildView.mm | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/widget/src/cocoa/nsChildView.mm b/widget/src/cocoa/nsChildView.mm
index fbf553cbc21e..35bf8de5a2ea 100644
--- a/widget/src/cocoa/nsChildView.mm
+++ b/widget/src/cocoa/nsChildView.mm
@@ -2617,7 +2617,14 @@ static const PRInt32 sShadowInvalidationInterval = 100;
   paintEvent.region = rgn;
 
   nsAutoRetainCocoaObject kungFuDeathGrip(self);
-  mGeckoChild->DispatchWindowEvent(paintEvent);
+  PRBool painted = mGeckoChild->DispatchWindowEvent(paintEvent);
+  if (!painted && [self isOpaque]) {
+    // Gecko refused to draw, but we've claimed to be opaque, so we have to
+    // draw something--fill with white.
+    CGContextSetRGBFillColor(aContext, 1, 1, 1, 1);
+    CGContextFillRect(aContext, CGRectMake(aRect.origin.x, aRect.origin.y,
+                                           aRect.size.width, aRect.size.height));
+  }
   if (!mGeckoChild)
     return;