SkSTArenaAlloc

Syntactic sugar, gets rid of some boilerplate.

Change-Id: Ibdb28b7a8f1d5e4a4e18c12d423b987d7194e340
Reviewed-on: https://skia-review.googlesource.com/17837
Commit-Queue: Florin Malita <fmalita@chromium.org>
Reviewed-by: Herb Derby <herb@google.com>
diff --git a/gm/SkLinearBitmapPipelineGM.cpp b/gm/SkLinearBitmapPipelineGM.cpp
index cab20d3..f07d2f7 100644
--- a/gm/SkLinearBitmapPipelineGM.cpp
+++ b/gm/SkLinearBitmapPipelineGM.cpp
@@ -115,8 +115,7 @@
     uint32_t flags = 0;
     auto procN = SkXfermode::GetD32Proc(SkBlendMode::kSrcOver, flags);
 
-    char storage[512];
-    SkArenaAlloc allocator{storage, sizeof(storage)};
+    SkSTArenaAlloc<512> allocator;
     SkLinearBitmapPipeline pipeline{
             inv, filterQuality,
             SkShader::kRepeat_TileMode, SkShader::kRepeat_TileMode,