Fix nsLayoutUtils::ComputeSizeWithIntrinsicDimensions to produce correct results when one of the tentative height/width (i.e., the intrinsic height/width) is 0. (Bug 677091) r=roc

When either the intrinsic width or the intrinsic height is 0, the
element does not have an intrinsic ratio, and thus the table that
ComputeAutoSizeWithIntrinsicDimensions is implementing technically
doesn't apply.  However, it can quite straightforwardly produce the
correct results despite that, if we correctly apply the
min/max-width/height properties.

layout/base/nsLayoutUtils.cpp

@@ -2762,8 +2762,7 @@ nsLayoutUtils::ComputeAutoSizeWithIntrinsicDimensions(nscoord minWidth, nscoord
     if (heightAtMinWidth > maxHeight)
       heightAtMinWidth = maxHeight;
   } else {
-    heightAtMaxWidth = tentHeight;
-    heightAtMinWidth = tentHeight;
+    heightAtMaxWidth = heightAtMinWidth = NS_CSS_MINMAX(tentHeight, minHeight, maxHeight);
   }
 
   if (tentHeight > 0) {
@@ -2774,8 +2773,7 @@ nsLayoutUtils::ComputeAutoSizeWithIntrinsicDimensions(nscoord minWidth, nscoord
     if (widthAtMinHeight > maxWidth)
       widthAtMinHeight = maxWidth;
   } else {
-    widthAtMaxHeight = tentWidth;
-    widthAtMinHeight = tentWidth;
+    widthAtMaxHeight = widthAtMinHeight = NS_CSS_MINMAX(tentWidth, minWidth, maxWidth);
   }
 
   // The table at http://www.w3.org/TR/CSS21/visudet.html#min-max-widths :