private iterator to visit all resource cache entries

src/core/SkGlyphCache.h

 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be found in the LICENSE file.
  */
 
 #ifndef SkGlyphCache_DEFINED
 #define SkGlyphCache_DEFINED
 
 #include "SkBitmap.h"
@@ skipping 48 matching lines @@
         existing cache entry. If not, ask the scalercontext to compute it for us.
     */
     uint16_t unicharToGlyph(SkUnichar);
 
     /** Map the glyph to its Unicode equivalent. Unmappable glyphs map to a character code of zero.
     */
     SkUnichar glyphToUnichar(uint16_t);
 
     /** Returns the number of glyphs for this strike.
     */
-    unsigned getGlyphCount();
+    unsigned getGlyphCount() const;
+
+    /** Return the number of glyphs currently cached. */
+    int countCachedGlyphs() const;
 
     /** Return the image associated with the glyph. If it has not been generated this will
         trigger that.
     */
     const void* findImage(const SkGlyph&);
 
     /** Return the Path associated with the glyph. If it has not been generated this will trigger
         that.
     */
     const SkPath* findPath(const SkGlyph&);
@@ skipping 51 matching lines @@
         descriptor, a different strike will be generated. This is fine. It does mean we can have
         more than 1 strike for the same descriptor, but that will eventually get purged, and the
         win is that different thread will never block each other while a strike is being used.
     */
     static SkGlyphCache* DetachCache(SkTypeface* typeface, const SkDescriptor* desc) {
         return VisitCache(typeface, desc, DetachProc, NULL);
     }
 
     static void Dump();
 
+    typedef void (*Visitor)(const SkGlyphCache&, void* context);
+    static void VisitAll(Visitor, void* context);
+
 #ifdef SK_DEBUG
     void validate() const;
 #else
     void validate() const {}
 #endif
 
     class AutoValidate : SkNoncopyable {
     public:
         AutoValidate(const SkGlyphCache* cache) : fCache(cache) {
             if (fCache) {
@@ skipping 149 matching lines @@
                             const SkMatrix* matrix) {
         fCache = paint.detachCache(surfaceProps, matrix, true);
     }
 
 private:
     SkAutoGlyphCacheNoGamma() : SkAutoGlyphCacheBase() {}
 };
 #define SkAutoGlyphCacheNoGamma(...) SK_REQUIRE_LOCAL_VAR(SkAutoGlyphCacheNoGamma)
 
 #endif