cleanup GrContext resource cache api

R=robertphillips@google.com

Author: bsalomon@google.com

Review URL: https://codereview.chromium.org/275563005

git-svn-id: http://skia.googlecode.com/svn/trunk@14669 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/samplecode/SampleApp.cpp b/samplecode/SampleApp.cpp
index 71fb8d3..8003a06 100644
--- a/samplecode/SampleApp.cpp
+++ b/samplecode/SampleApp.cpp
@@ -1863,10 +1863,10 @@
             {
                 GrContext* grContext = this->getGrContext();
                 if (grContext) {
-                    size_t cacheBytes = grContext->getGpuTextureCacheBytes();
+                    size_t cacheBytes;
+                    grContext->getResourceCacheUsage(NULL, &cacheBytes);
                     grContext->freeGpuResources();
-                    SkDebugf("Purged %d bytes from the GPU resource cache.\n",
-                             cacheBytes);
+                    SkDebugf("Purged %d bytes from the GPU resource cache.\n", cacheBytes);
                 }
             }
             return true;