Update from https://crrev.com/317530

cc/surfaces/display.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/surfaces/display.h"
 
 #include "base/message_loop/message_loop.h"
 #include "base/trace_event/trace_event.h"
 #include "cc/debug/benchmark_instrumentation.h"
 #include "cc/output/compositor_frame.h"
@@ skipping 116 matching lines @@
   benchmark_instrumentation::IssueDisplayRenderingStatsEvent();
 
   // Run callbacks early to allow pipelining.
   for (const auto& id_entry : aggregator_->previous_contained_surfaces()) {
     Surface* surface = manager_->GetSurfaceForId(id_entry.first);
     if (surface)
       surface->RunDrawCallbacks(SurfaceDrawStatus::DRAWN);
   }
   DelegatedFrameData* frame_data = frame->delegated_frame_data.get();
 
-  gfx::Size surface_size =
-      frame_data->render_pass_list.back()->output_rect.size();
+  frame->metadata.latency_info.insert(frame->metadata.latency_info.end(),
+                                      stored_latency_info_.begin(),
+                                      stored_latency_info_.end());
+  stored_latency_info_.clear();
+  bool have_copy_requests = false;
+  for (const auto* pass : frame_data->render_pass_list) {
+    have_copy_requests |= !pass->copy_requests.empty();
+  }
 
-  gfx::Rect device_viewport_rect = gfx::Rect(current_surface_size_);
-  gfx::Rect device_clip_rect = device_viewport_rect;
-  bool disable_picture_quad_image_filtering = false;
+  gfx::Size surface_size;
+  bool have_damage = false;
+  if (!frame_data->render_pass_list.empty()) {
+    surface_size = frame_data->render_pass_list.back()->output_rect.size();
+    have_damage =
+        !frame_data->render_pass_list.back()->damage_rect.size().IsEmpty();
+  }
+  bool avoid_swap = surface_size != current_surface_size_;
+  bool should_draw = !frame->metadata.latency_info.empty() ||
+                     have_copy_requests || (have_damage && !avoid_swap);
 
-  renderer_->DecideRenderPassAllocationsForFrame(frame_data->render_pass_list);
-  renderer_->DrawFrame(&frame_data->render_pass_list,
-                       device_scale_factor_,
-                       device_viewport_rect,
-                       device_clip_rect,
-                       disable_picture_quad_image_filtering);
+  if (should_draw) {
+    gfx::Rect device_viewport_rect = gfx::Rect(current_surface_size_);
+    gfx::Rect device_clip_rect = device_viewport_rect;
+    bool disable_picture_quad_image_filtering = false;
 
-  if (surface_size != current_surface_size_) {
+    renderer_->DecideRenderPassAllocationsForFrame(
+        frame_data->render_pass_list);
+    renderer_->DrawFrame(&frame_data->render_pass_list, device_scale_factor_,
+                         device_viewport_rect, device_clip_rect,
+                         disable_picture_quad_image_filtering);
+  }
+
+  if (should_draw && !avoid_swap) {
+    renderer_->SwapBuffers(frame->metadata);
+  } else {
+    stored_latency_info_.insert(stored_latency_info_.end(),
+                                frame->metadata.latency_info.begin(),
+                                frame->metadata.latency_info.end());
     DidSwapBuffers();
     DidSwapBuffersComplete();
-  } else {
-    renderer_->SwapBuffers(frame->metadata);
   }
 
   return true;
 }
 
 void Display::DidSwapBuffers() {
   client_->DidSwapBuffers();
 }
 
 void Display::DidSwapBuffersComplete() {
@@ skipping 33 matching lines @@
 
 int Display::GetMaxFramesPending() {
   int max_frames_pending =
       output_surface_ ? output_surface_->capabilities().max_frames_pending : 0;
   if (max_frames_pending <= 0)
     max_frames_pending = OutputSurface::DEFAULT_MAX_FRAMES_PENDING;
   return max_frames_pending;
 }
 
 }  // namespace cc