cc: Move UnoccludedContentRect to Occlusion.

cc/trees/occlusion_tracker_perftest.cc

Index: cc/trees/occlusion_tracker_perftest.cc
diff --git a/cc/trees/occlusion_tracker_perftest.cc b/cc/trees/occlusion_tracker_perftest.cc
index d9130746de716f1d4cf68f9efd2f0bb4e71609c2..14a9ffd272d18baa7e2179330f52c765055118f0 100644
--- a/cc/trees/occlusion_tracker_perftest.cc
+++ b/cc/trees/occlusion_tracker_perftest.cc
@@ -106,11 +106,13 @@ TEST_F(OcclusionTrackerPerfTest, UnoccludedContentRect_FullyOccluded) {
   transform_to_target.Translate(0, 96);
 
   do {
+    Occlusion occlusion =
+        tracker.GetCurrentOcclusionForLayer(transform_to_target);
     for (int x = 0; x < viewport_rect.width(); x += 256) {
       for (int y = 0; y < viewport_rect.height(); y += 256) {
         gfx::Rect query_content_rect(x, y, 256, 256);
-        gfx::Rect unoccluded = tracker.UnoccludedContentRect(
-            query_content_rect, transform_to_target);
+        gfx::Rect unoccluded =
+            occlusion.GetUnoccludedContentRect(query_content_rect);
         // Sanity test that we're not hitting early outs.
         bool expect_empty =
             query_content_rect.right() <= viewport_rect.width() &&
@@ -181,11 +183,13 @@ TEST_F(OcclusionTrackerPerfTest, UnoccludedContentRect_10OpaqueLayers) {
   transform_to_target.Translate(0, 96);
 
   do {
+    Occlusion occlusion =
+        tracker.GetCurrentOcclusionForLayer(transform_to_target);
     for (int x = 0; x < viewport_rect.width(); x += 256) {
       for (int y = 0; y < viewport_rect.height(); y += 256) {
         gfx::Rect query_content_rect(x, y, 256, 256);
-        gfx::Rect unoccluded = tracker.UnoccludedContentRect(
-            query_content_rect, transform_to_target);
+        gfx::Rect unoccluded =
+            occlusion.GetUnoccludedContentRect(query_content_rect);
       }
     }