Speculative revert to diagnose crash in chrome. Revert "Add SkCachedData and use it for SkMipMap"

src/core/SkCachedData.h

Index: src/core/SkCachedData.h
diff --git a/src/core/SkCachedData.h b/src/core/SkCachedData.h
deleted file mode 100644
index 886ca3e7e44cdbec055bf01b731cfe69ded96002..0000000000000000000000000000000000000000
--- a/src/core/SkCachedData.h
+++ /dev/null
@@ -1,107 +0,0 @@
-/*
- * Copyright 2014 Google Inc.
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-#ifndef SkCachedData_DEFINED
-#define SkCachedData_DEFINED
-
-#include "SkThread.h"
-
-class SkDiscardableMemory;
-
-class SkCachedData : ::SkNoncopyable {
-public:
-    SkCachedData(void* mallocData, size_t size);
-    SkCachedData(size_t size, SkDiscardableMemory*);
-    virtual ~SkCachedData();
-
-    size_t size() const { return fSize; }
-    const void* data() const { return fData; }
-
-    void* writable_data() { return fData; }
-
-    void ref() const { this->internalRef(false); }
-    void unref() const { this->internalUnref(false); }
-
-    int testing_only_getRefCnt() const { return fRefCnt; }
-    bool testing_only_isLocked() const { return fIsLocked; }
-    bool testing_only_isInCache() const { return fInCache; }
-
-protected:
-    // called when fData changes. could be NULL.
-    virtual void onDataChange(void* oldData, void* newData) {}
-
-private:
-    SkMutex fMutex;     // could use a pool of these...
-
-    enum StorageType {
-        kDiscardableMemory_StorageType,
-        kMalloc_StorageType
-    };
-
-    union {
-        SkDiscardableMemory*    fDM;
-        void*                   fMalloc;
-    } fStorage;
-    void*       fData;
-    size_t      fSize;
-    int         fRefCnt;    // low-bit means we're owned by the cache
-    StorageType fStorageType;
-    bool        fInCache;
-    bool        fIsLocked;
-
-    void internalRef(bool fromCache) const;
-    void internalUnref(bool fromCache) const;
-
-    void inMutexRef(bool fromCache);
-    bool inMutexUnref(bool fromCache);  // returns true if we should delete "this"
-    void inMutexLock();
-    void inMutexUnlock();
-
-    // called whenever our fData might change (lock or unlock)
-    void setData(void* newData) {
-        if (newData != fData) {
-            // notify our subclasses of the change
-            this->onDataChange(fData, newData);
-            fData = newData;
-        }
-    }
-
-    class AutoMutexWritable;
-
-public:
-#ifdef SK_DEBUG
-    void validate() const;
-#else
-    void validate() const {}
-#endif
-    
-   /*
-     *  Attaching a data to to a SkResourceCache (only one at a time) enables the data to be
-     *  unlocked when the cache is the only owner, thus freeing it to be purged (assuming the
-     *  data is backed by a SkDiscardableMemory).
-     *
-     *  When attached, it also automatically attempts to "lock" the data when the first client
-     *  ref's the data (typically from a find(key, visitor) call).
-     *
-     *  Thus the data will always be "locked" when a non-cache has a ref on it (whether or not
-     *  the lock succeeded to recover the memory -- check data() to see if it is NULL).
-     */
-
-    /*
-     *  Call when adding this instance to a SkResourceCache::Rec subclass
-     *  (typically in the Rec's constructor).
-     */
-    void attachToCacheAndRef() const { this->internalRef(true); }
-
-    /*
-     *  Call when removing this instance from a SkResourceCache::Rec subclass
-     *  (typically in the Rec's destructor).
-     */
-    void detachFromCacheAndUnref() const { this->internalUnref(true); }
-};
-
-#endif