refactored where texture descriptors are made for metal gpu backend

Bug: skia:
Change-Id: Ic90660b5ad5c1e795cd768bb7471e9ac80a59f47
Reviewed-on: https://skia-review.googlesource.com/138999
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Timothy Liang <timliang@google.com>
diff --git a/src/gpu/mtl/GrMtlTexture.h b/src/gpu/mtl/GrMtlTexture.h
index 99fb27d..2265b72 100644
--- a/src/gpu/mtl/GrMtlTexture.h
+++ b/src/gpu/mtl/GrMtlTexture.h
@@ -17,7 +17,9 @@
 class GrMtlTexture : public GrTexture {
 public:
     static sk_sp<GrMtlTexture> CreateNewTexture(GrMtlGpu*, SkBudgeted budgeted,
-                                                const GrSurfaceDesc&, int mipLevels);
+                                                const GrSurfaceDesc&,
+                                                MTLTextureDescriptor*,
+                                                GrMipMapsStatus);
 
     static sk_sp<GrMtlTexture> MakeWrappedTexture(GrMtlGpu*, const GrSurfaceDesc&,
                                                   id<MTLTexture>);