Web Animations: Support animation of flood-opacity

LayoutTests/animations/interpolation/svg-flood-opacity-interpolation.html

Index: LayoutTests/animations/interpolation/svg-flood-opacity-interpolation.html
diff --git a/LayoutTests/animations/interpolation/svg-flood-color-interpolation.html b/LayoutTests/animations/interpolation/svg-flood-opacity-interpolation.html
old mode 100644
new mode 100755
similarity index 51%
copy from LayoutTests/animations/interpolation/svg-flood-color-interpolation.html
copy to LayoutTests/animations/interpolation/svg-flood-opacity-interpolation.html
index 94fa59f9ec3e5f478362f420d6d3f4a64b48ddbe..05f69d429328bc75b16fa9087d45e2a1d2eab795
--- a/LayoutTests/animations/interpolation/svg-flood-color-interpolation.html
+++ b/LayoutTests/animations/interpolation/svg-flood-opacity-interpolation.html
@@ -4,6 +4,7 @@
 svg {
   width: 100px;
   height: 100px;
+  background: red;
 }
 svg rect {
   fill: black;
@@ -15,7 +16,7 @@ svg rect {
   <svg>
     <defs>
       <filter id="test">
-        <feFlood class="target"></feFlood>
+        <feFlood x="10" y="10" width="80" height="80" flood-color="blue" class="target" />
       </filter>
     </defs>
     <rect width="100" height="100"></rect>
@@ -24,17 +25,17 @@ svg rect {
 <script src="resources/interpolation-test.js"></script>
 <script>
 assertInterpolation({
-  property: 'flood-color',
-  from: 'orange',
-  to: 'blue'
+  property: 'flood-opacity',
+  from: '0.25',
+  to: '0.75'
 }, [
-  {at: -5, is: '#ffff00'},
-  {at: -0.4, is: '#ffe700'},
-  {at: 0, is: 'orange'}, // ffa500
-  {at: 0.2, is: '#cc8433'},
-  {at: 0.6, is: '#664299'},
-  {at: 1, is: 'blue'}, // 0000ff
-  {at: 1.5, is: 'blue'}
+  {at: -1, is: '0'}, // SVG Opacity ranges from 0.0 to 1.0
+  {at: -0.25, is: '0.125'},
+  {at: 0, is: '0.25'},
+  {at: 0.25, is: '0.375'},
+  {at: 1, is: '0.75'},
+  {at: 1.25, is: '0.875'},
+  {at: 2, is: '1'}, // SVG Opacity ranges from 0.0 to 1.0
 ]);
 </script>
 </body>