[Impeller] clang-tidy fixes

impeller/renderer/backend/gles/render_pass_gles.cc

@@ -100,7 +100,7 @@ void ConfigureStencil(const ProcTableGLES& gl,
   gl.Enable(GL_STENCIL_TEST);
   const auto& front = pipeline.GetFrontStencilAttachmentDescriptor();
   const auto& back = pipeline.GetBackStencilAttachmentDescriptor();
-  if (front == back) {
+  if (front.has_value() && front == back) {
     ConfigureStencil(GL_FRONT_AND_BACK, gl, *front, stencil_reference);
   } else if (front.has_value()) {
     ConfigureStencil(GL_FRONT, gl, *front, stencil_reference);

impeller/renderer/backend/vulkan/command_encoder_vk.cc

@@ -14,8 +14,9 @@ namespace impeller {
 
 class TrackedObjectsVK {
  public:
-  explicit TrackedObjectsVK(std::weak_ptr<const DeviceHolder> device_holder,
-                            const std::shared_ptr<CommandPoolVK>& pool)
+  explicit TrackedObjectsVK(
+      const std::weak_ptr<const DeviceHolder>& device_holder,
+      const std::shared_ptr<CommandPoolVK>& pool)
       : desc_pool_(device_holder) {
     if (!pool) {
       return;
@@ -96,7 +97,7 @@ class TrackedObjectsVK {
 };
 
 CommandEncoderVK::CommandEncoderVK(
-    std::weak_ptr<const DeviceHolder> device_holder,
+    const std::weak_ptr<const DeviceHolder>& device_holder,
     const std::shared_ptr<QueueVK>& queue,
     const std::shared_ptr<CommandPoolVK>& pool,
     std::shared_ptr<FenceWaiterVK> fence_waiter)

impeller/renderer/backend/vulkan/command_encoder_vk.h

@@ -76,7 +76,7 @@ class CommandEncoderVK {
   std::shared_ptr<TrackedObjectsVK> tracked_objects_;
   bool is_valid_ = false;
 
-  CommandEncoderVK(std::weak_ptr<const DeviceHolder> device_holder,
+  CommandEncoderVK(const std::weak_ptr<const DeviceHolder>& device_holder,
                    const std::shared_ptr<QueueVK>& queue,
                    const std::shared_ptr<CommandPoolVK>& pool,
                    std::shared_ptr<FenceWaiterVK> fence_waiter);

impeller/renderer/backend/vulkan/context_vk.cc

@@ -227,7 +227,7 @@ void ContextVK::Setup(Settings settings) {
       VALIDATION_LOG << "No valid Vulkan device found.";
       return;
     }
-    device_holder->physical_device = std::move(physical_device.value());
+    device_holder->physical_device = physical_device.value();
   }
 
   //----------------------------------------------------------------------------

impeller/renderer/backend/vulkan/descriptor_pool_vk.cc

@@ -10,7 +10,7 @@
 namespace impeller {
 
 DescriptorPoolVK::DescriptorPoolVK(
-    std::weak_ptr<const DeviceHolder> device_holder)
+    const std::weak_ptr<const DeviceHolder>& device_holder)
     : device_holder_(device_holder) {
   FML_DCHECK(device_holder.lock());
 }

impeller/renderer/backend/vulkan/descriptor_pool_vk.h

@@ -27,7 +27,8 @@ namespace impeller {
 ///
 class DescriptorPoolVK {
  public:
-  explicit DescriptorPoolVK(std::weak_ptr<const DeviceHolder> device_holder);
+  explicit DescriptorPoolVK(
+      const std::weak_ptr<const DeviceHolder>& device_holder);
 
   ~DescriptorPoolVK();
 

impeller/renderer/backend/vulkan/fence_waiter_vk.cc

@@ -12,7 +12,7 @@
 namespace impeller {
 
 FenceWaiterVK::FenceWaiterVK(std::weak_ptr<DeviceHolder> device_holder)
-    : device_holder_(device_holder) {
+    : device_holder_(std::move(device_holder)) {
   waiter_thread_ = std::make_unique<std::thread>([&]() { Main(); });
   is_valid_ = true;
 }
@@ -81,7 +81,7 @@ void FenceWaiterVK::Main() {
 }
 
 std::optional<std::vector<vk::Fence>> FenceWaiterVK::TrimAndCreateWaitSetLocked(
-    std::shared_ptr<DeviceHolder> device_holder) {
+    const std::shared_ptr<DeviceHolder>& device_holder) {
   if (terminate_) {
     return std::nullopt;
   }

impeller/renderer/backend/vulkan/fence_waiter_vk.h

@@ -47,7 +47,7 @@ class FenceWaiterVK {
   void Main();
 
   std::optional<std::vector<vk::Fence>> TrimAndCreateWaitSetLocked(
-      std::shared_ptr<DeviceHolder> device_holder);
+      const std::shared_ptr<DeviceHolder>& device_holder);
 
   FML_DISALLOW_COPY_AND_ASSIGN(FenceWaiterVK);
 };

impeller/renderer/backend/vulkan/pipeline_vk.cc

@@ -14,7 +14,7 @@ PipelineVK::PipelineVK(std::weak_ptr<DeviceHolder> device_holder,
                        vk::UniquePipelineLayout layout,
                        vk::UniqueDescriptorSetLayout descriptor_set_layout)
     : Pipeline(std::move(library), desc),
-      device_holder_(device_holder),
+      device_holder_(std::move(device_holder)),
       pipeline_(std::move(pipeline)),
       render_pass_(std::move(render_pass)),
       layout_(std::move(layout)),

impeller/renderer/backend/vulkan/shader_library_vk.cc

@@ -55,7 +55,7 @@ static std::string VKShaderNameToShaderKeyName(const std::string& name,
 ShaderLibraryVK::ShaderLibraryVK(
     std::weak_ptr<DeviceHolder> device_holder,
     const std::vector<std::shared_ptr<fml::Mapping>>& shader_libraries_data)
-    : device_holder_(device_holder) {
+    : device_holder_(std::move(device_holder)) {
   TRACE_EVENT0("impeller", "CreateShaderLibrary");
   bool success = true;
   auto iterator = [&](auto type,         //