Fixes the rendering of a SVG filter (e.g. feFlood) by testing against total

Source/platform/graphics/filters/FilterEffect.cpp

Index: Source/platform/graphics/filters/FilterEffect.cpp
diff --git a/Source/platform/graphics/filters/FilterEffect.cpp b/Source/platform/graphics/filters/FilterEffect.cpp
index ce8f23f723481bd38b66d3446078b5c987ae6b66..f98698fcce391d3dae1619c1e9963f8effc4005e 100644
--- a/Source/platform/graphics/filters/FilterEffect.cpp
+++ b/Source/platform/graphics/filters/FilterEffect.cpp
@@ -36,6 +36,8 @@
 
 namespace WebCore {
 
+static const float kMaxFilterArea = 4096 * 4096;
+
 FilterEffect::FilterEffect(Filter* filter)
     : m_alphaImage(false)
     , m_filter(filter)
@@ -54,14 +56,26 @@ FilterEffect::~FilterEffect()
 {
 }
 
-inline bool isFilterSizeValid(IntRect rect)
+float FilterEffect::maxFilterArea()
 {
-    if (rect.width() < 0 || rect.width() > kMaxFilterSize
-        || rect.height() < 0 || rect.height() > kMaxFilterSize)
+    return kMaxFilterArea;
+}
+
+bool FilterEffect::isFilterSizeValid(const FloatRect& rect)
+{
+    if (rect.width() < 0 || rect.height() < 0
+        ||  (rect.height() * rect.width() > kMaxFilterArea))
         return false;
+
     return true;
 }
 
+
+bool FilterEffect::isFilterSizeValid(const IntRect& rect)
+{
+    return isFilterSizeValid(FloatRect(rect));
+}
+
 FloatRect FilterEffect::determineAbsolutePaintRect(const FloatRect& originalRequestedRect)
 {
     FloatRect requestedRect = originalRequestedRect;