cc: Make visible rect computation aware of pixel-moving filters

cc/layers/render_surface_impl.cc

Index: cc/layers/render_surface_impl.cc
diff --git a/cc/layers/render_surface_impl.cc b/cc/layers/render_surface_impl.cc
index 4a08fa1de9a109f3b0023fcac80ad6cfc3eebf04..edacc1a09ce394087ac946ed70562ca1035c691c 100644
--- a/cc/layers/render_surface_impl.cc
+++ b/cc/layers/render_surface_impl.cc
@@ -190,6 +190,17 @@ void RenderSurfaceImpl::SetContentRectForTesting(const gfx::Rect& rect) {
   SetContentRect(rect);
 }
 
+gfx::Rect RenderSurfaceImpl::CalculateExpandedClipForFilters(
+    const gfx::Transform& target_to_surface) {
+  gfx::Rect clip_in_surface_space =
+      MathUtil::ProjectEnclosingClippedRect(target_to_surface, clip_rect());
+  gfx::Rect expanded_clip_in_surface_space = Filters().MapRectReverse(
+      clip_in_surface_space, FiltersTransform().matrix());
+  gfx::Rect expanded_clip_in_target_space = MathUtil::MapEnclosingClippedRect(
+      draw_transform(), expanded_clip_in_surface_space);
+  return expanded_clip_in_target_space;
+}
+
 gfx::Rect RenderSurfaceImpl::CalculateClippedAccumulatedContentRect() {
   if (HasCopyRequest() || !is_clipped())
     return accumulated_content_rect();
@@ -214,7 +225,13 @@ gfx::Rect RenderSurfaceImpl::CalculateClippedAccumulatedContentRect() {
   if (clip_rect().Contains(accumulated_rect_in_target_space))
     return accumulated_content_rect();
 
-  gfx::Rect clipped_accumulated_rect_in_target_space = clip_rect();
+  gfx::Rect clipped_accumulated_rect_in_target_space;
+  if (Filters().HasFilterThatMovesPixels()) {
+    clipped_accumulated_rect_in_target_space =
+        CalculateExpandedClipForFilters(target_to_surface);
+  } else {
+    clipped_accumulated_rect_in_target_space = clip_rect();
+  }
   clipped_accumulated_rect_in_target_space.Intersect(
       accumulated_rect_in_target_space);