cc: Fix overlay damage tracking bug

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 a1d3a65a8a11b6b1eb17f7e7edb0d52442f3e90e..7009789d66a5f517717f2a57dec2ebf8365831a9 100644
--- a/cc/output/direct_renderer.cc
+++ b/cc/output/direct_renderer.cc
@@ -207,8 +207,7 @@ 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.Union(overlay_processor_->GetAndResetOverlayDamage());
   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;
@@ -238,62 +237,44 @@ void DirectRenderer::DrawFrame(RenderPassList* render_passes_in_draw_order,
     frame.overlay_list.push_back(output_surface_plane);
   }
 
-  // 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()) {
-    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;
-        }
-        overlay_processor_->ProcessForOverlays(
-            resource_provider_, render_passes_in_draw_order,
-            &frame.overlay_list, &frame.root_damage_rect);
-      }
+  // If we have any copy requests, we can't remove any quads for overlays or
+  // CALayers because the framebuffer would be missing the removed quads'
+  // contents.
+  bool has_copy_requests = false;
+  for (auto* pass : *render_passes_in_draw_order) {
+    if (!pass->copy_requests.empty()) {
+      has_copy_requests = true;
+      break;
     }
   }
+  if (!has_copy_requests) {
+    overlay_processor_->ProcessForOverlays(
+        resource_provider_, render_passes_in_draw_order, &frame.overlay_list,
+        &frame.ca_layer_overlay_list, &frame.root_damage_rect);
+  }
 
-  for (size_t i = 0; i < render_passes_in_draw_order->size(); ++i) {
-    RenderPass* pass = render_passes_in_draw_order->at(i);
-    DrawRenderPass(&frame, pass);
-
-    for (ScopedPtrVector<CopyOutputRequest>::iterator it =
-             pass->copy_requests.begin();
-         it != pass->copy_requests.end();
-         ++it) {
-      if (it != pass->copy_requests.begin()) {
-        // Doing a readback is destructive of our state on Mac, so make sure
-        // we restore the state between readbacks. http://crbug.com/99393.
-        UseRenderPass(&frame, pass);
+  // If all damage is being drawn with overlays or CALayers then skip drawing
+  // the render passes.
+  if (frame.root_damage_rect.IsEmpty() && !has_copy_requests) {
+    BindFramebufferToOutputSurface(&frame);
+  } else {
+    for (size_t i = 0; i < render_passes_in_draw_order->size(); ++i) {
+      RenderPass* pass = render_passes_in_draw_order->at(i);
+      DrawRenderPass(&frame, pass);
+
+      for (ScopedPtrVector<CopyOutputRequest>::iterator it =
+               pass->copy_requests.begin();
+           it != pass->copy_requests.end(); ++it) {
+        if (it != pass->copy_requests.begin()) {
+          // Doing a readback is destructive of our state on Mac, so make sure
+          // we restore the state between readbacks. http://crbug.com/99393.
+          UseRenderPass(&frame, pass);
+        }
+        CopyCurrentRenderPassToBitmap(&frame, pass->copy_requests.take(it));
       }
-      CopyCurrentRenderPassToBitmap(&frame, pass->copy_requests.take(it));
     }
   }
   FinishDrawingFrame(&frame);
-
   render_passes_in_draw_order->clear();
 }