Revert of Make SkSmallAllocator obey the RAII invariants and be expandable

src/core/SkBlitter.cpp

Index: src/core/SkBlitter.cpp
diff --git a/src/core/SkBlitter.cpp b/src/core/SkBlitter.cpp
index 35a213b8b74b30fc1fd0ee953f6bc3c27142212b..b81432533b06966fa27ec83ebf3ed9a254b64cb9 100644
--- a/src/core/SkBlitter.cpp
+++ b/src/core/SkBlitter.cpp
@@ -896,15 +896,14 @@
         size_t contextSize = shader->contextSize(rec);
         if (contextSize) {
             // Try to create the ShaderContext
-            shaderContext = allocator->createWithIniter(
-                contextSize,
-                [&rec, shader](void* storage) {
-                    return shader->createContext(rec, storage);
-                });
+            void* storage = allocator->reserveT<SkShader::Context>(contextSize);
+            shaderContext = shader->createContext(rec, storage);
             if (!shaderContext) {
+                allocator->freeLast();
                 return allocator->createT<SkNullBlitter>();
             }
             SkASSERT(shaderContext);
+            SkASSERT((void*) shaderContext == storage);
         } else {
             return allocator->createT<SkNullBlitter>();
         }