Fix issue where SkAutoSTMalloc doesn't default initialize std::unique_ptr.

TBR=jvanverth@google.com

Change-Id: Ifd29f55956f640dfc972490244d5d356bac89759
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/225418
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
diff --git a/src/gpu/GrResourceProvider.cpp b/src/gpu/GrResourceProvider.cpp
index e4b01c2..c5ec22f 100644
--- a/src/gpu/GrResourceProvider.cpp
+++ b/src/gpu/GrResourceProvider.cpp
@@ -58,7 +58,7 @@
     }
 
     SkAutoSTMalloc<14, GrMipLevel> tmpTexels;
-    SkAutoSTMalloc<14, std::unique_ptr<char[]>> tmpDatas;
+    SkAutoSTArray<14, std::unique_ptr<char[]>> tmpDatas;
     if (mipLevelCount > 0 && texels) {
         tmpTexels.reset(mipLevelCount);
         tmpDatas.reset(mipLevelCount);