[Fuchsia] Synchronize image access in OutputPresenterFuchsia

Image access in OutputPresenterImages was not synchronized because
need_synchronization() was false int he images it uses.
Updated OutputPresenterFuchsia to set SCANOUT image usage bit and also
updated ExternalVkImageBacking::need_synchronization() to return true
for SCANOUT images. This ensures that image access in
OutputPresenterFuchsia properly.

Also fixed semaphore ownership handling in OutputPresenterFuchsia.

Bug: 1115692
Change-Id: Ibf375845eab2fbf320f777f45adcc98719ee239c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2353413
Commit-Queue: Sergey Ulanov <sergeyu@chromium.org>
Auto-Submit: Sergey Ulanov <sergeyu@chromium.org>
Reviewed-by: Peng Huang <penghuang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#798127}

components/viz/service/display_embedder/output_presenter_fuchsia.cc

@@ -312,7 +312,8 @@ OutputPresenterFuchsia::AllocateImages(gfx::ColorSpace color_space,
   collection->Close();
 
   // Create PresenterImageFuchsia for each buffer in the collection.
-  uint32_t image_usage = gpu::SHARED_IMAGE_USAGE_RASTER;
+  uint32_t image_usage =
+      gpu::SHARED_IMAGE_USAGE_RASTER | gpu::SHARED_IMAGE_USAGE_SCANOUT;
   if (vulkan->enforce_protected_memory())
     image_usage |= gpu::SHARED_IMAGE_USAGE_PROTECTED;
 
@@ -412,6 +413,8 @@ void OutputPresenterFuchsia::SchedulePrimaryPlane(
   std::vector<GrBackendSemaphore> read_begin_semaphores;
   std::vector<GrBackendSemaphore> read_end_semaphores;
   image_fuchsia->TakeSemaphores(&read_begin_semaphores, &read_end_semaphores);
+  DCHECK(!read_begin_semaphores.empty());
+  DCHECK(!read_end_semaphores.empty());
 
   auto* vulkan_context_provider = dependency_->GetVulkanContextProvider();
   auto* vulkan_implementation =
@@ -423,13 +426,6 @@ void OutputPresenterFuchsia::SchedulePrimaryPlane(
                          read_begin_semaphores, &(next_frame_->acquire_fences));
   GrSemaphoresToZxEvents(vulkan_implementation, vk_device, read_end_semaphores,
                          &(next_frame_->release_fences));
-
-  // Destroy |read_begin_semaphores|, but not |read_end_semaphores|, since
-  // SharedImageRepresentationSkia::BeginScopedReadAccess() keeps ownership of
-  // the end_semaphores.
-  for (auto& semaphore : read_begin_semaphores) {
-    vkDestroySemaphore(vk_device, semaphore.vkSemaphore(), nullptr);
-  }
 }
 
 std::vector<OutputPresenter::OverlayData>

gpu/command_buffer/service/external_vk_image_backing.h

@@ -103,6 +103,11 @@ class ExternalVkImageBacking final : public ClearTrackingSharedImageBacking {
     if (usage() & SHARED_IMAGE_USAGE_GLES2) {
       return !use_separate_gl_texture() && (texture_ || texture_passthrough_);
     }
+
+    if (usage() & SHARED_IMAGE_USAGE_SCANOUT) {
+      return true;
+    }
+
     return false;
   }
   uint32_t reads_in_progress() const { return reads_in_progress_; }