Update uniteIfNonZero to use isZero.

https://bugs.webkit.org/show_bug.cgi?id=76637

Patch by Philip Rogers <pdr@google.com> on 2012-01-23
Reviewed by Darin Adler.

No new tests. (I found no existing codepath that would be affected by
this change but I think this change is still valuable in preventing
future bugs.)

* platform/graphics/FloatRect.cpp:
(WebCore::FloatRect::uniteIfNonZero):

The following change is a minor followup to
https://bugs.webkit.org/show_bug.cgi?id=76177#c12 and is not directly
related to the rest of this patch.
* rendering/svg/SVGRenderSupport.cpp:
(WebCore::SVGRenderSupport::computeContainerBoundingBoxes):

Canonical link: https://commits.webkit.org/93677@main
git-svn-id: https://svn.webkit.org/repository/webkit/trunk@105643 268f45cc-cd09-0410-ab3c-d52691b4dbfc

Source/WebCore/ChangeLog

@@ -1,3 +1,23 @@
+2012-01-23  Philip Rogers  <pdr@google.com>
+
+        Update uniteIfNonZero to use isZero.
+        https://bugs.webkit.org/show_bug.cgi?id=76637
+
+        Reviewed by Darin Adler.
+
+        No new tests. (I found no existing codepath that would be affected by
+        this change but I think this change is still valuable in preventing
+        future bugs.)
+
+        * platform/graphics/FloatRect.cpp:
+        (WebCore::FloatRect::uniteIfNonZero):
+
+        The following change is a minor followup to
+        https://bugs.webkit.org/show_bug.cgi?id=76177#c12 and is not directly
+        related to the rest of this patch.
+        * rendering/svg/SVGRenderSupport.cpp:
+        (WebCore::SVGRenderSupport::computeContainerBoundingBoxes):
+
 2012-01-23  Antti Koivisto  <antti@apple.com>
 
         Eliminate CSSElementStyleDeclaration

Source/WebCore/platform/graphics/FloatRect.cpp

@@ -119,9 +119,9 @@ void FloatRect::uniteEvenIfEmpty(const FloatRect& other)
 void FloatRect::uniteIfNonZero(const FloatRect& other)
 {
     // Handle empty special cases first.
-    if (!other.width() && !other.height())
+    if (other.isZero())
         return;
-    if (!width() && !height()) {
+    if (isZero()) {
         *this = other;
         return;
     }

Source/WebCore/rendering/svg/SVGRenderSupport.cpp

@@ -190,8 +190,7 @@ void SVGRenderSupport::computeContainerBoundingBoxes(const RenderObject* contain
             repaintBoundingBox.unite(transform.mapRect(current->repaintRectInLocalCoordinates()));
         }
 
-        if (isFirstChild)
-            isFirstChild = false;
+        isFirstChild = false;
     }
 }