2009-04-25 Dirk Schulze <krit@webkit.org>

        Reviewed by Oliver Hunt.

        A width or height of zero for the destination or source rect of an
        image causes a not invertible pattern matrix.
        This crahes newer versions of Cairo and give some graphic gliches in
        Canvas.
        With this patch we check if there is something to draw and return if not.

        * platform/graphics/cairo/ImageCairo.cpp:
        (WebCore::BitmapImage::draw):


git-svn-id: svn://svn.chromium.org/blink/trunk@42875 bbb929c8-8fbe-4397-9dbb-9b2b20218538

third_party/WebKit/WebCore/ChangeLog

+2009-04-25  Dirk Schulze  <krit@webkit.org>
+
+        Reviewed by Oliver Hunt.
+
+        A width or height of zero for the destination or source rect of an
+        image causes a not invertible pattern matrix.
+        This crahes newer versions of Cairo and give some graphic gliches in
+        Canvas.
+        With this patch we check if there is something to draw and return if not.
+
+        * platform/graphics/cairo/ImageCairo.cpp:
+        (WebCore::BitmapImage::draw):
+
 2009-04-25  Simon Fraser  <simon.fraser@apple.com>
 
         Reviewed by Darin Adler

third_party/WebKit/WebCore/platform/graphics/cairo/ImageCairo.cpp

@@ -89,15 +89,19 @@ BitmapImage::BitmapImage(cairo_surface_t* surface, ImageObserver* observer)
 
 void BitmapImage::draw(GraphicsContext* context, const FloatRect& dst, const FloatRect& src, CompositeOperator op)
 {
+    FloatRect srcRect(src);
+    FloatRect dstRect(dst);
+
+    if (dstRect.width() == 0.0f || dstRect.height() == 0.0f ||
+        srcRect.width() == 0.0f || srcRect.height() == 0.0f)
+        return;
+
     startAnimation();
 
     cairo_surface_t* image = frameAtIndex(m_currentFrame);
     if (!image) // If it's too early we won't have an image yet.
         return;
 
-    FloatRect srcRect(src);
-    FloatRect dstRect(dst);
-
     if (mayFillWithSolidColor()) {
         fillWithSolidColor(context, dstRect, solidColor(), op);
         return;