Expose writing to mip levels via GrSurfaceContext::writePixels

Bug: skia:11786
Change-Id: Id17952db0aede56fa39845d9d371cf0a141f9dd7
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/391836
Commit-Queue: Brian Salomon <bsalomon@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>
diff --git a/src/gpu/GrProxyProvider.cpp b/src/gpu/GrProxyProvider.cpp
index 9562f07..08d0964 100644
--- a/src/gpu/GrProxyProvider.cpp
+++ b/src/gpu/GrProxyProvider.cpp
@@ -324,7 +324,7 @@
     sk_sp<GrTextureProxy> proxy = this->createLazyProxy(
             [bitmap](GrResourceProvider* resourceProvider, const LazySurfaceDesc& desc) {
                 SkASSERT(desc.fMipmapped == GrMipmapped::kNo);
-                GrMipLevel mipLevel = { bitmap.getPixels(), bitmap.rowBytes() };
+                GrMipLevel mipLevel = {bitmap.getPixels(), bitmap.rowBytes(), nullptr};
                 auto colorType = SkColorTypeToGrColorType(bitmap.colorType());
                 return LazyCallbackResult(resourceProvider->createTexture(
                         desc.fDimensions, desc.fFormat, colorType, desc.fRenderable,