ozone: dri: add synchronous SwapBuffers support on surfaceless

ui/ozone/platform/dri/hardware_display_controller.cc

Index: ui/ozone/platform/dri/hardware_display_controller.cc
diff --git a/ui/ozone/platform/dri/hardware_display_controller.cc b/ui/ozone/platform/dri/hardware_display_controller.cc
index 0bd49477e857fcabbd05c7c4a4ec1a41bf88c5dc..5e8bcbf608bfedfaeeff93b5c527dd7176cfa98a 100644
--- a/ui/ozone/platform/dri/hardware_display_controller.cc
+++ b/ui/ozone/platform/dri/hardware_display_controller.cc
@@ -105,7 +105,28 @@ bool HardwareDisplayController::SchedulePageFlip(
   if (HasPendingPageFlips())
     return true;
 
-  bool status = ActualSchedulePageFlip();
+  bool status = ActualSchedulePageFlip(false);
+
+  // No page flip event on failure so discard failed request.
+  if (!status)
+    requests_.pop_front();
+
+  return status;
+}
+
+bool HardwareDisplayController::PageFlip() {

[dnicoara, 2015/02/26 18:22:21]

I think you can just use SchedulePageFlip() for this and just add the |is_sync|
parameter. You can stash the |is_sync| parameter in the PageFlipRequest() as
well to deal with transitions between synchronous and asynchronous modes.

+  CHECK(!HasPendingPageFlips());
+  TRACE_EVENT0("dri", "HDC::PageFlip");
+
+  // Ignore requests with no planes to schedule.
+  if (pending_planes_.empty())
+    return true;
+
+  requests_.push_back(
+      PageFlipRequest(pending_planes_, base::Bind(&base::DoNothing)));
+  pending_planes_.clear();
+
+  bool status = ActualSchedulePageFlip(true);
 
   // No page flip event on failure so discard failed request.
   if (!status)
@@ -246,7 +267,7 @@ void HardwareDisplayController::OnPageFlipEvent() {
     return;
 
   // At this point we still have requests pending, so schedule the next request.
-  bool status = ActualSchedulePageFlip();
+  bool status = ActualSchedulePageFlip(false);
   if (!status) {
     PageFlipRequest request = requests_.front();
     requests_.pop_front();
@@ -274,7 +295,7 @@ bool HardwareDisplayController::HasPendingPageFlips() const {
   return false;
 }
 
-bool HardwareDisplayController::ActualSchedulePageFlip() {
+bool HardwareDisplayController::ActualSchedulePageFlip(bool is_sync) {
   TRACE_EVENT0("dri", "HDC::ActualSchedulePageFlip");
   DCHECK(!requests_.empty());
 
@@ -297,7 +318,7 @@ bool HardwareDisplayController::ActualSchedulePageFlip() {
   }
 
   for (const auto& planes : owned_hardware_planes_) {
-    if (!planes.first->plane_manager()->Commit(planes.second)) {
+    if (!planes.first->plane_manager()->Commit(planes.second, is_sync)) {
       status = false;
     }
   }