[dawn][native] Assert Pipeline Is Set Before Applying Immediates

Replace early return with an assertion to ensure that the pipeline is
set before applying immediate constants in D3D11, D3D12, and Vulkan
backends.

This change helps catch potential issues where immediate constants are
attempted to be applied without a valid pipeline.

Bug: 366291600
Change-Id: Icf4f988909ac63933056b18031206f6201f9cc75
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/282215
Commit-Queue: Shaobo Yan <shaoboyan@microsoft.com>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>

Author: shaoboyan091

src/dawn/native/d3d11/CommandBufferD3D11.cpp

@@ -224,12 +224,9 @@ class ImmediateConstantTracker : public T {
     ImmediateConstantTracker() = default;
 
     MaybeError Apply(const ScopedSwapStateCommandRecordingContext* commandContext) {
-        auto* lastPipeline = this->mLastPipeline;
-        if (!lastPipeline) {
-            return {};
-        }
+        DAWN_ASSERT(this->mLastPipeline != nullptr);
 
-        ImmediateConstantMask pipelineMask = lastPipeline->GetImmediateMask();
+        ImmediateConstantMask pipelineMask = this->mLastPipeline->GetImmediateMask();
         ImmediateConstantMask uploadBits = this->mDirty & pipelineMask;
         for (auto&& [offset, size] : IterateRanges(uploadBits)) {
             uint32_t immediateContentStartOffset =

src/dawn/native/d3d12/CommandBufferD3D12.cpp

@@ -414,9 +414,9 @@ class ImmediateConstantTracker : public T {
 
     // Calling this after BindGroupTrackerBase::Apply() to update root signature.
     void Apply(CommandRecordingContext* commandContext) {
-        auto* lastPipeline = this->mLastPipeline;
-        DAWN_ASSERT(lastPipeline != nullptr);
+        DAWN_ASSERT(this->mLastPipeline != nullptr);
 
+        auto* lastPipeline = this->mLastPipeline;
         ImmediateConstantMask pipelineMask = lastPipeline->GetImmediateMask();
         ImmediateConstantMask uploadBits = this->mDirty & pipelineMask;
         for (auto&& [offset, size] : IterateRanges(uploadBits)) {

src/dawn/native/vulkan/CommandBufferVk.cpp

@@ -231,11 +231,9 @@ class ImmediateConstantTracker : public T {
     ImmediateConstantTracker() = default;
 
     void Apply(Device* device, VkCommandBuffer commandBuffer) {
-        auto* lastPipeline = this->mLastPipeline;
-        if (!lastPipeline) {
-            return;
-        }
+        DAWN_ASSERT(this->mLastPipeline != nullptr);
 
+        auto* lastPipeline = this->mLastPipeline;
         const ImmediateConstantMask& pipelineMask = lastPipeline->GetImmediateMask();
         ImmediateConstantMask uploadBits = this->mDirty & lastPipeline->GetImmediateMask();
         for (auto&& [offset, size] : IterateRanges(uploadBits)) {