[WebGPU] GPUQueue.writeTexture adds layout offset twice

https://bugs.webkit.org/show_bug.cgi?id=263001
<radar://116791102>

Reviewed by Tadeu Zagallo.

The offset is already added at the JS layer. We don't
need to add it again in the GPU process. It is better
to add any offsets at the JS layer because less data
needs to be sent from the web content process to the gpu
process.

* Source/WebGPU/WebGPU/Queue.mm:
(WebGPU::Queue::writeTexture):

Canonical link: https://commits.webkit.org/269237@main

Source/WebGPU/WebGPU/Queue.mm

@@ -307,11 +307,9 @@ static bool validateWriteTexture(const WGPUImageCopyTexture& destination, const
 
     // https://gpuweb.github.io/gpuweb/#dom-gpuqueue-writetexture
 
-    auto dataByteSize = dataSize;
-
     const auto& texture = fromAPI(destination.texture);
 
-    if (!validateWriteTexture(destination, dataLayout, size, dataByteSize, texture)) {
+    if (!validateWriteTexture(destination, dataLayout, size, dataSize, texture)) {
         m_device.generateAValidationError("Validation failure."_s);
         return;
     }
@@ -355,7 +353,7 @@ static bool validateWriteTexture(const WGPUImageCopyTexture& destination, const
                 case WGPUTextureDimension_1D: {
                     auto region = MTLRegionMake1D(destination.origin.x, size.width);
                     for (uint32_t layer = 0; layer < size.depthOrArrayLayers; ++layer) {
-                        auto sourceOffset = static_cast<NSUInteger>(dataLayout.offset + layer * bytesPerImage);
+                        auto sourceOffset = static_cast<NSUInteger>(layer * bytesPerImage);
                         NSUInteger destinationSlice = destination.origin.z + layer;
                         [fromAPI(destination.texture).texture()
                             replaceRegion:region
@@ -370,7 +368,7 @@ static bool validateWriteTexture(const WGPUImageCopyTexture& destination, const
                 case WGPUTextureDimension_2D: {
                     auto region = MTLRegionMake2D(destination.origin.x, destination.origin.y, size.width, size.height);
                     for (uint32_t layer = 0; layer < size.depthOrArrayLayers; ++layer) {
-                        auto sourceOffset = static_cast<NSUInteger>(dataLayout.offset + layer * bytesPerImage);
+                        auto sourceOffset = static_cast<NSUInteger>(layer * bytesPerImage);
                         NSUInteger destinationSlice = destination.origin.z + layer;
                         [fromAPI(destination.texture).texture()
                             replaceRegion:region
@@ -384,12 +382,11 @@ static bool validateWriteTexture(const WGPUImageCopyTexture& destination, const
                 }
                 case WGPUTextureDimension_3D: {
                     auto region = MTLRegionMake3D(destination.origin.x, destination.origin.y, destination.origin.z, size.width, size.height, size.depthOrArrayLayers);
-                    auto sourceOffset = static_cast<NSUInteger>(dataLayout.offset);
                     [fromAPI(destination.texture).texture()
                         replaceRegion:region
                         mipmapLevel:destination.mipLevel
                         slice:0
-                        withBytes:static_cast<const char*>(data) + sourceOffset
+                        withBytes:static_cast<const char*>(data)
                         bytesPerRow:bytesPerRow
                         bytesPerImage:bytesPerImage];
                     break;
@@ -409,13 +406,13 @@ static bool validateWriteTexture(const WGPUImageCopyTexture& destination, const
         }
     }
 
-    ensureBlitCommandEncoder();
     // FIXME(PERFORMANCE): Suballocate, so the common case doesn't need to hit the kernel.
     // FIXME(PERFORMANCE): Should this temporary buffer really be shared?
-    id<MTLBuffer> temporaryBuffer = [m_device.device() newBufferWithBytes:static_cast<const char*>(data) + dataLayout.offset length:static_cast<NSUInteger>(dataByteSize) options:MTLResourceStorageModeShared];
+    id<MTLBuffer> temporaryBuffer = [m_device.device() newBufferWithBytes:static_cast<const char*>(data) length:static_cast<NSUInteger>(dataSize) options:MTLResourceStorageModeShared];
     if (!temporaryBuffer)
         return;
 
+    ensureBlitCommandEncoder();
     auto logicalSize = fromAPI(destination.texture).logicalMiplevelSpecificTextureExtent(destination.mipLevel);
     auto widthForMetal = std::min(size.width, logicalSize.width);
     auto heightForMetal = std::min(size.height, logicalSize.height);