Revert of Extract most of the mutable state of SkShader into a separate Context object.

src/core/SkSmallAllocator.h

Index: src/core/SkSmallAllocator.h
diff --git a/src/core/SkSmallAllocator.h b/src/core/SkSmallAllocator.h
index 8d4b53a707d9db9c56fa3eaa16fb1b6ca7b7ae85..655008b70698ec5262e91c26ce22f9145c85239a 100644
--- a/src/core/SkSmallAllocator.h
+++ b/src/core/SkSmallAllocator.h
@@ -117,12 +117,10 @@
             // but we're not sure we can catch all callers, so handle it but
             // assert false in debug mode.
             SkASSERT(false);
-            rec->fStorageSize = 0;
             rec->fHeapStorage = sk_malloc_throw(storageRequired);
             rec->fObj = static_cast<void*>(rec->fHeapStorage);
         } else {
             // There is space in fStorage.
-            rec->fStorageSize = storageRequired;
             rec->fHeapStorage = NULL;
             SkASSERT(SkIsAlign4(fStorageUsed));
             rec->fObj = static_cast<void*>(fStorage + (fStorageUsed / 4));
@@ -133,26 +131,11 @@
         return rec->fObj;
     }
 
-    /*
-     *  Free the memory reserved last without calling the destructor.
-     *  Can be used in a nested way, i.e. after reserving A and B, calling
-     *  freeLast once will free B and calling it again will free A.
-     */
-    void freeLast() {
-        SkASSERT(fNumObjects > 0);
-        Rec* rec = &fRecs[fNumObjects - 1];
-        sk_free(rec->fHeapStorage);
-        fStorageUsed -= rec->fStorageSize;
-
-        fNumObjects--;
-    }
-
 private:
     struct Rec {
-        size_t fStorageSize;  // 0 if allocated on heap
-        void*  fObj;
-        void*  fHeapStorage;
-        void   (*fKillProc)(void*);
+        void* fObj;
+        void* fHeapStorage;
+        void  (*fKillProc)(void*);
     };
 
     // Number of bytes used so far.