[cc] Fix CompositorFrameSinkSupport BeginFrameAck interface.

components/exo/surface.cc

 // Copyright 2015 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 "components/exo/surface.h"
 
 #include <utility>
 
 #include "base/callback_helpers.h"
 #include "base/logging.h"
@@ skipping 820 matching lines @@
                       gfx::Transform());
 
   gfx::Rect quad_rect = output_rect;
   cc::SharedQuadState* quad_state =
       render_pass->CreateAndAppendSharedQuadState();
   quad_state->quad_layer_bounds = contents_surface_size;
   quad_state->visible_quad_layer_rect = quad_rect;
   quad_state->opacity = state_.alpha;
 
   cc::CompositorFrame frame;
-  current_begin_frame_ack_.has_damage = true;
+  // If we commit while we don't have an active BeginFrame, we acknowledge a
+  // manual one.
+  if (current_begin_frame_ack_.sequence_number ==
+      cc::BeginFrameArgs::kInvalidFrameNumber) {
+    current_begin_frame_ack_ = cc::BeginFrameAck::CreateManualAckWithDamage();
+  } else {
+    current_begin_frame_ack_.has_damage = true;
+  }
   frame.metadata.begin_frame_ack = current_begin_frame_ack_;
 
   if (current_resource_.id) {
     // Texture quad is only needed if buffer is not fully transparent.
     if (state_.alpha) {
       cc::TextureDrawQuad* texture_quad =
           render_pass->CreateAndAppendDrawQuad<cc::TextureDrawQuad>();
       float vertex_opacity[4] = {1.0, 1.0, 1.0, 1.0};
       gfx::Rect opaque_rect;
       if (!current_resource_has_alpha_ ||
@@ skipping 17 matching lines @@
         render_pass->CreateAndAppendDrawQuad<cc::SolidColorDrawQuad>();
     solid_quad->SetNew(quad_state, quad_rect, quad_rect, SK_ColorBLACK, false);
   }
 
   frame.render_pass_list.push_back(std::move(render_pass));
   compositor_frame_sink_holder_->GetCompositorFrameSink()
       ->SubmitCompositorFrame(local_surface_id_, std::move(frame));
 }
 
 }  // namespace exo