[Impeller] Make DeviceHolder follow convention for backend specific utilities. (#51300)

Utilities below the HAL that are backend specific have the VK (in case of Vulkan) suffix. The only class that doesn't follow this convention is/was DeviceHolder. This caused some confusion when reading code leading to wondering what a device holder above the HAL was supposed to do/mean. Adds the VK suffix to device holder with a docstring. Also adds the file the source set as it was missing.

No change in functionality. Just a rename of an existing class.

Author: chinmaygarde

ci/licenses_golden/licenses_flutter

@@ -38103,7 +38103,7 @@ ORIGIN: ../../../flutter/impeller/renderer/backend/vulkan/descriptor_pool_vk.cc
 ORIGIN: ../../../flutter/impeller/renderer/backend/vulkan/descriptor_pool_vk.h + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/impeller/renderer/backend/vulkan/device_buffer_vk.cc + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/impeller/renderer/backend/vulkan/device_buffer_vk.h + ../../../flutter/LICENSE
-ORIGIN: ../../../flutter/impeller/renderer/backend/vulkan/device_holder.h + ../../../flutter/LICENSE
+ORIGIN: ../../../flutter/impeller/renderer/backend/vulkan/device_holder_vk.h + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/impeller/renderer/backend/vulkan/fence_waiter_vk.cc + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/impeller/renderer/backend/vulkan/fence_waiter_vk.h + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/impeller/renderer/backend/vulkan/formats_vk.cc + ../../../flutter/LICENSE
@@ -40954,7 +40954,7 @@ FILE: ../../../flutter/impeller/renderer/backend/vulkan/descriptor_pool_vk.cc
 FILE: ../../../flutter/impeller/renderer/backend/vulkan/descriptor_pool_vk.h
 FILE: ../../../flutter/impeller/renderer/backend/vulkan/device_buffer_vk.cc
 FILE: ../../../flutter/impeller/renderer/backend/vulkan/device_buffer_vk.h
-FILE: ../../../flutter/impeller/renderer/backend/vulkan/device_holder.h
+FILE: ../../../flutter/impeller/renderer/backend/vulkan/device_holder_vk.h
 FILE: ../../../flutter/impeller/renderer/backend/vulkan/fence_waiter_vk.cc
 FILE: ../../../flutter/impeller/renderer/backend/vulkan/fence_waiter_vk.h
 FILE: ../../../flutter/impeller/renderer/backend/vulkan/formats_vk.cc

impeller/renderer/backend/vulkan/BUILD.gn

@@ -64,6 +64,7 @@ impeller_component("vulkan") {
     "descriptor_pool_vk.h",
     "device_buffer_vk.cc",
     "device_buffer_vk.h",
+    "device_holder_vk.h",
     "fence_waiter_vk.cc",
     "fence_waiter_vk.h",
     "formats_vk.cc",

impeller/renderer/backend/vulkan/allocator_vk.cc

@@ -94,7 +94,7 @@ static PoolVMA CreateBufferPool(VmaAllocator allocator) {
 AllocatorVK::AllocatorVK(std::weak_ptr<Context> context,
                          uint32_t vulkan_api_version,
                          const vk::PhysicalDevice& physical_device,
-                         const std::shared_ptr<DeviceHolder>& device_holder,
+                         const std::shared_ptr<DeviceHolderVK>& device_holder,
                          const vk::Instance& instance,
                          const CapabilitiesVK& capabilities)
     : context_(std::move(context)), device_holder_(device_holder) {

impeller/renderer/backend/vulkan/allocator_vk.h

@@ -10,7 +10,7 @@
 #include "impeller/core/allocator.h"
 #include "impeller/renderer/backend/vulkan/context_vk.h"
 #include "impeller/renderer/backend/vulkan/device_buffer_vk.h"
-#include "impeller/renderer/backend/vulkan/device_holder.h"
+#include "impeller/renderer/backend/vulkan/device_holder_vk.h"
 #include "impeller/renderer/backend/vulkan/vk.h"
 
 #include <array>
@@ -33,7 +33,7 @@ class AllocatorVK final : public Allocator {
   UniqueAllocatorVMA allocator_;
   UniquePoolVMA staging_buffer_pool_;
   std::weak_ptr<Context> context_;
-  std::weak_ptr<DeviceHolder> device_holder_;
+  std::weak_ptr<DeviceHolderVK> device_holder_;
   ISize max_texture_size_;
   bool is_valid_ = false;
   bool supports_memoryless_textures_ = false;
@@ -44,7 +44,7 @@ class AllocatorVK final : public Allocator {
   AllocatorVK(std::weak_ptr<Context> context,
               uint32_t vulkan_api_version,
               const vk::PhysicalDevice& physical_device,
-              const std::shared_ptr<DeviceHolder>& device_holder,
+              const std::shared_ptr<DeviceHolderVK>& device_holder,
               const vk::Instance& instance,
               const CapabilitiesVK& capabilities);
 

impeller/renderer/backend/vulkan/command_encoder_vk.cc

@@ -66,7 +66,7 @@ std::shared_ptr<CommandEncoderVK> CommandEncoderFactoryVK::Create() {
 }
 
 CommandEncoderVK::CommandEncoderVK(
-    std::weak_ptr<const DeviceHolder> device_holder,
+    std::weak_ptr<const DeviceHolderVK> device_holder,
     std::shared_ptr<TrackedObjectsVK> tracked_objects,
     const std::shared_ptr<QueueVK>& queue,
     std::shared_ptr<FenceWaiterVK> fence_waiter)

impeller/renderer/backend/vulkan/command_encoder_vk.h

@@ -13,7 +13,7 @@
 #include "impeller/renderer/backend/vulkan/command_queue_vk.h"
 #include "impeller/renderer/backend/vulkan/context_vk.h"
 #include "impeller/renderer/backend/vulkan/descriptor_pool_vk.h"
-#include "impeller/renderer/backend/vulkan/device_holder.h"
+#include "impeller/renderer/backend/vulkan/device_holder_vk.h"
 #include "impeller/renderer/backend/vulkan/queue_vk.h"
 #include "impeller/renderer/backend/vulkan/shared_object_vk.h"
 #include "impeller/renderer/backend/vulkan/vk.h"
@@ -52,7 +52,7 @@ class CommandEncoderVK {
   using SubmitCallback = std::function<void(bool)>;
 
   // Visible for testing.
-  CommandEncoderVK(std::weak_ptr<const DeviceHolder> device_holder,
+  CommandEncoderVK(std::weak_ptr<const DeviceHolderVK> device_holder,
                    std::shared_ptr<TrackedObjectsVK> tracked_objects,
                    const std::shared_ptr<QueueVK>& queue,
                    std::shared_ptr<FenceWaiterVK> fence_waiter);
@@ -91,7 +91,7 @@ class CommandEncoderVK {
   friend class ContextVK;
   friend class CommandQueueVK;
 
-  std::weak_ptr<const DeviceHolder> device_holder_;
+  std::weak_ptr<const DeviceHolderVK> device_holder_;
   std::shared_ptr<TrackedObjectsVK> tracked_objects_;
   std::shared_ptr<QueueVK> queue_;
   const std::shared_ptr<FenceWaiterVK> fence_waiter_;

impeller/renderer/backend/vulkan/compute_pipeline_vk.cc

@@ -7,7 +7,7 @@
 namespace impeller {
 
 ComputePipelineVK::ComputePipelineVK(
-    std::weak_ptr<DeviceHolder> device_holder,
+    std::weak_ptr<DeviceHolderVK> device_holder,
     std::weak_ptr<PipelineLibrary> library,
     const ComputePipelineDescriptor& desc,
     vk::UniquePipeline pipeline,
@@ -22,7 +22,7 @@ ComputePipelineVK::ComputePipelineVK(
 }
 
 ComputePipelineVK::~ComputePipelineVK() {
-  std::shared_ptr<DeviceHolder> device_holder = device_holder_.lock();
+  std::shared_ptr<DeviceHolderVK> device_holder = device_holder_.lock();
   if (device_holder) {
     descriptor_set_layout_.reset();
     layout_.reset();

impeller/renderer/backend/vulkan/compute_pipeline_vk.h

@@ -9,7 +9,7 @@
 
 #include "flutter/fml/macros.h"
 #include "impeller/base/backend_cast.h"
-#include "impeller/renderer/backend/vulkan/device_holder.h"
+#include "impeller/renderer/backend/vulkan/device_holder_vk.h"
 #include "impeller/renderer/backend/vulkan/vk.h"
 #include "impeller/renderer/pipeline.h"
 
@@ -20,7 +20,7 @@ class ComputePipelineVK final
       public BackendCast<ComputePipelineVK,
                          Pipeline<ComputePipelineDescriptor>> {
  public:
-  ComputePipelineVK(std::weak_ptr<DeviceHolder> device_holder,
+  ComputePipelineVK(std::weak_ptr<DeviceHolderVK> device_holder,
                     std::weak_ptr<PipelineLibrary> library,
                     const ComputePipelineDescriptor& desc,
                     vk::UniquePipeline pipeline,
@@ -39,7 +39,7 @@ class ComputePipelineVK final
  private:
   friend class PipelineLibraryVK;
 
-  std::weak_ptr<DeviceHolder> device_holder_;
+  std::weak_ptr<DeviceHolderVK> device_holder_;
   vk::UniquePipeline pipeline_;
   vk::UniquePipelineLayout layout_;
   vk::UniqueDescriptorSetLayout descriptor_set_layout_;

impeller/renderer/backend/vulkan/context_vk.h

@@ -14,7 +14,7 @@
 #include "impeller/base/backend_cast.h"
 #include "impeller/core/formats.h"
 #include "impeller/renderer/backend/vulkan/command_pool_vk.h"
-#include "impeller/renderer/backend/vulkan/device_holder.h"
+#include "impeller/renderer/backend/vulkan/device_holder_vk.h"
 #include "impeller/renderer/backend/vulkan/pipeline_library_vk.h"
 #include "impeller/renderer/backend/vulkan/queue_vk.h"
 #include "impeller/renderer/backend/vulkan/sampler_library_vk.h"
@@ -130,7 +130,7 @@ class ContextVK final : public Context,
     return true;
   }
 
-  std::shared_ptr<DeviceHolder> GetDeviceHolder() const {
+  std::shared_ptr<DeviceHolderVK> GetDeviceHolder() const {
     return device_holder_;
   }
 
@@ -164,7 +164,7 @@ class ContextVK final : public Context,
   void InitializeCommonlyUsedShadersIfNeeded() const override;
 
  private:
-  struct DeviceHolderImpl : public DeviceHolder {
+  struct DeviceHolderImpl : public DeviceHolderVK {
     // |DeviceHolder|
     const vk::Device& GetDevice() const override { return device.get(); }
     // |DeviceHolder|