Revert of Make SkSmallAllocator obey the RAII invariants and be expandable

src/core/SkCanvas.cpp

Index: src/core/SkCanvas.cpp
diff --git a/src/core/SkCanvas.cpp b/src/core/SkCanvas.cpp
index aa984502aa3273459d10833ac246493c1e06dcf4..cd4dcbc2a509349838e5957b76f4535f00083c0c 100644
--- a/src/core/SkCanvas.cpp
+++ b/src/core/SkCanvas.cpp
@@ -495,11 +495,9 @@
         }
 
         if (SkDrawLooper* looper = paint.getLooper()) {
-            fLooperContext = fLooperContextAllocator.createWithIniter(
-                looper->contextSize(),
-                [&](void* buffer) {
-                    return looper->createContext(canvas, buffer);
-                });
+            void* buffer = fLooperContextAllocator.reserveT<SkDrawLooper::Context>(
+                    looper->contextSize());
+            fLooperContext = looper->createContext(canvas, buffer);
             fIsSimple = false;
         } else {
             fLooperContext = nullptr;