private iterator to visit all resource cache entries

samplecode/SampleApp.cpp

Index: samplecode/SampleApp.cpp
diff --git a/samplecode/SampleApp.cpp b/samplecode/SampleApp.cpp
index 2d12bfd67293bbaccc9107befbdb11d3ad6e317a..ca9b733f9573c3648d0f5a2d11c3b45bb03ae3d1 100644
--- a/samplecode/SampleApp.cpp
+++ b/samplecode/SampleApp.cpp
@@ -1415,9 +1415,18 @@ bool SampleWindow::previousSample() {
     return true;
 }
 
+#include "SkResourceCache.h"
+#include "SkGlyphCache.h"
 bool SampleWindow::nextSample() {
     fCurrIndex = (fCurrIndex + 1) % fSamples.count();
     this->loadView((*fSamples[fCurrIndex])());
+
+    if (false) {
+        SkResourceCache::TestDumpMemoryStatistics();
+        SkGlyphCache::Dump();
+        SkDebugf("\n");
+    }
+
     return true;
 }