Vulkan: Use absl::flat_hash_set in mappableBuffersForEagerTransition

Bug: dawn:1513
Change-Id: Id3a5b1547d4dd27e7db56a5f863eb8d2cd9d514b
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/185382
Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Jiawei Shao <jiawei.shao@intel.com>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
diff --git a/src/dawn/native/vulkan/BufferVk.cpp b/src/dawn/native/vulkan/BufferVk.cpp
index 1853dc7..57a3f12 100644
--- a/src/dawn/native/vulkan/BufferVk.cpp
+++ b/src/dawn/native/vulkan/BufferVk.cpp
@@ -733,7 +733,7 @@
 // static
 void Buffer::TransitionMappableBuffersEagerly(const VulkanFunctions& fn,
                                               CommandRecordingContext* recordingContext,
-                                              const std::set<Ref<Buffer>>& buffers) {
+                                              const absl::flat_hash_set<Ref<Buffer>>& buffers) {
     DAWN_ASSERT(!buffers.empty());
 
     VkPipelineStageFlags srcStages = 0;
diff --git a/src/dawn/native/vulkan/BufferVk.h b/src/dawn/native/vulkan/BufferVk.h
index 3676539..14b1642 100644
--- a/src/dawn/native/vulkan/BufferVk.h
+++ b/src/dawn/native/vulkan/BufferVk.h
@@ -28,11 +28,10 @@
 #ifndef SRC_DAWN_NATIVE_VULKAN_BUFFERVK_H_
 #define SRC_DAWN_NATIVE_VULKAN_BUFFERVK_H_
 
-#include <set>
-
 #include "dawn/native/Buffer.h"
 #include "partition_alloc/pointers/raw_ptr.h"
 
+#include "absl/container/flat_hash_set.h"
 #include "dawn/common/SerialQueue.h"
 #include "dawn/common/vulkan_platform.h"
 #include "dawn/native/ResourceMemoryAllocation.h"
@@ -76,7 +75,7 @@
 
     static void TransitionMappableBuffersEagerly(const VulkanFunctions& fn,
                                                  CommandRecordingContext* recordingContext,
-                                                 const std::set<Ref<Buffer>>& buffers);
+                                                 const absl::flat_hash_set<Ref<Buffer>>& buffers);
 
   private:
     ~Buffer() override;
diff --git a/src/dawn/native/vulkan/CommandRecordingContext.h b/src/dawn/native/vulkan/CommandRecordingContext.h
index 671c4e7..a40d32d 100644
--- a/src/dawn/native/vulkan/CommandRecordingContext.h
+++ b/src/dawn/native/vulkan/CommandRecordingContext.h
@@ -27,7 +27,6 @@
 #ifndef SRC_DAWN_NATIVE_VULKAN_COMMANDRECORDINGCONTEXT_H_
 #define SRC_DAWN_NATIVE_VULKAN_COMMANDRECORDINGCONTEXT_H_
 
-#include <set>
 #include <vector>
 
 #include "absl/container/flat_hash_set.h"
@@ -65,7 +64,7 @@
 
     // Mappable buffers which will be eagerly transitioned to usage MapRead or MapWrite after
     // VkSubmit.
-    std::set<Ref<Buffer>> mappableBuffersForEagerTransition;
+    absl::flat_hash_set<Ref<Buffer>> mappableBuffersForEagerTransition;
 
     // For Device state tracking only.
     VkCommandPool commandPool = VK_NULL_HANDLE;