[Merge to 2883] mac: Fix bug where opacity is applied twice on RenderPassDrawQuads.

content/test/data/gpu/filter_effects.html

Index: content/test/data/gpu/filter_effects.html
diff --git a/content/test/data/gpu/filter_effects.html b/content/test/data/gpu/filter_effects.html
index 8150397192da8eed2de5a75b86a8bc75e0de6e5f..8c5973119030efe5d520c893365abf1dea7ca4bf 100644
--- a/content/test/data/gpu/filter_effects.html
+++ b/content/test/data/gpu/filter_effects.html
@@ -79,6 +79,10 @@ body {
   from {-webkit-filter: opacity(70%)}
   to {-webkit-filter: opacity(70%)}
 }
+@-webkit-keyframes do-nothing-anim {
+  from {-webkit-filter: hue-rotate(0deg)}
+  to {-webkit-filter: hue-rotate(0deg)}
+}
 .gradient {
   float: left;
   height: 50px;
@@ -110,6 +114,9 @@ body {
       </canvas>
   <canvas class="gradient" style="-webkit-animation: drop-shadow-anim 150000s;
       transform: scale(1.3, 0.8);"></canvas>
+  <div style="opacity: 0.7;">
+    <canvas class="gradient" style="-webkit-animation: do-nothing-anim 150000s;"></canvas>
+  </div>
 </div>
 </body>