cc: Fork OverlayCandidate to CALayerOverlay

cc/output/direct_renderer.cc

Index: cc/output/direct_renderer.cc
diff --git a/cc/output/direct_renderer.cc b/cc/output/direct_renderer.cc
index 16dcd5a3d3c35a8379c12ebb79ec20b9a6afec34..a1d3a65a8a11b6b1eb17f7e7edb0d52442f3e90e 100644
--- a/cc/output/direct_renderer.cc
+++ b/cc/output/direct_renderer.cc
@@ -207,6 +207,8 @@ void DirectRenderer::DrawFrame(RenderPassList* render_passes_in_draw_order,
   frame.root_damage_rect = Capabilities().using_partial_swap
                                ? root_render_pass->damage_rect
                                : root_render_pass->output_rect;
+  frame.root_damage_rect.Union(next_root_damage_rect_);
+  next_root_damage_rect_ = gfx::Rect();
   frame.root_damage_rect.Intersect(gfx::Rect(device_viewport_rect.size()));
   frame.device_viewport_rect = device_viewport_rect;
   frame.device_clip_rect = device_clip_rect;
@@ -239,26 +241,37 @@ void DirectRenderer::DrawFrame(RenderPassList* render_passes_in_draw_order,
   // If we have any copy requests, we can't remove any quads for overlays,
   // otherwise the framebuffer will be missing the overlay contents.
   if (root_render_pass->copy_requests.empty()) {
-    overlay_processor_->ProcessForOverlays(
-        resource_provider_, render_passes_in_draw_order, &frame.overlay_list,
-        &frame.root_damage_rect);
-
-    // No need to render in case the damage rect is completely composited using
-    // overlays and dont have any copy requests.
-    if (frame.root_damage_rect.IsEmpty()) {
-      bool handle_copy_requests = false;
-      for (auto* pass : *render_passes_in_draw_order) {
-        if (!pass->copy_requests.empty()) {
-          handle_copy_requests = true;
-          break;
+    if (overlay_processor_->ProcessForCALayers(
+            resource_provider_, render_passes_in_draw_order,
+            &frame.ca_layer_overlay_list, &frame.overlay_list)) {
+      // Ensure that the next frame to use the backbuffer will do a full redraw.
+      next_root_damage_rect_.Union(root_render_pass->output_rect);
+    } else {
+      overlay_processor_->ProcessForOverlays(
+          resource_provider_, render_passes_in_draw_order, &frame.overlay_list,
+          &frame.root_damage_rect);
+
+      // No need to render in case the damage rect is completely composited
+      // using
+      // overlays and dont have any copy requests.
+      if (frame.root_damage_rect.IsEmpty()) {
+        bool handle_copy_requests = false;
+        for (auto* pass : *render_passes_in_draw_order) {
+          if (!pass->copy_requests.empty()) {
+            handle_copy_requests = true;
+            break;
+          }
         }
-      }
 
-      if (!handle_copy_requests) {
-        BindFramebufferToOutputSurface(&frame);
-        FinishDrawingFrame(&frame);
-        render_passes_in_draw_order->clear();
-        return;
+        if (!handle_copy_requests) {
+          BindFramebufferToOutputSurface(&frame);
+          FinishDrawingFrame(&frame);
+          render_passes_in_draw_order->clear();
+          return;
+        }
+        overlay_processor_->ProcessForOverlays(
+            resource_provider_, render_passes_in_draw_order,
+            &frame.overlay_list, &frame.root_damage_rect);
       }
     }
   }