[Chromecast] Fix assert failure + add test in SwapWithBounds path

cc/output/gl_renderer.cc

 // Copyright 2010 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/output/gl_renderer.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 2432 matching lines @@
   if (use_sync_query_) {
     DCHECK(current_sync_query_);
     current_sync_query_->End();
     pending_sync_queries_.push_back(std::move(current_sync_query_));
   }
 
   swap_buffer_rect_.Union(current_frame()->root_damage_rect);
   if (overdraw_feedback_)
     FlushOverdrawFeedback(swap_buffer_rect_);
 
+  if (use_swap_with_bounds_)
+    swap_content_bounds_ = current_frame()->root_content_bounds;
+
   current_framebuffer_lock_ = nullptr;
 
   gl_->Disable(GL_BLEND);
   blend_shadow_ = false;
 
   ScheduleCALayers();
   ScheduleDCLayers();
   ScheduleOverlays();
 }
 
@@ skipping 144 matching lines @@
 
   TRACE_EVENT0("cc", "GLRenderer::SwapBuffers");
   // We're done! Time to swapbuffers!
 
   gfx::Size surface_size = surface_size_for_swap_buffers();
 
   OutputSurfaceFrame output_frame;
   output_frame.latency_info = std::move(latency_info);
   output_frame.size = surface_size;
   if (use_swap_with_bounds_) {
-    output_frame.content_bounds = current_frame()->root_content_bounds;
+    output_frame.content_bounds = std::move(swap_content_bounds_);
   } else if (use_partial_swap_) {
     // If supported, we can save significant bandwidth by only swapping the
     // damaged/scissored region (clamped to the viewport).
     swap_buffer_rect_.Intersect(gfx::Rect(surface_size));
     int flipped_y_pos_of_rect_bottom = surface_size.height() -
                                        swap_buffer_rect_.y() -
                                        swap_buffer_rect_.height();
     output_frame.sub_buffer_rect =
         gfx::Rect(swap_buffer_rect_.x(),
                   FlippedRootFramebuffer() ? flipped_y_pos_of_rect_bottom
@@ skipping 958 matching lines @@
     return;
 
   // Report GPU overdraw as a percentage of |max_result|.
   TRACE_COUNTER1(
       TRACE_DISABLED_BY_DEFAULT("cc.debug.overdraw"), "GPU Overdraw",
       (std::accumulate(overdraw->begin(), overdraw->end(), 0) * 100) /
           max_result);
 }
 
 }  // namespace cc