Don't call purgeCache() from within GrResource memebers.

R=robertphillips@google.com

Review URL: https://codereview.chromium.org/14864020

git-svn-id: http://skia.googlecode.com/svn/trunk@9102 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/GrResourceCache.h b/src/gpu/GrResourceCache.h
index f05ba98..c4ead34 100644
--- a/src/gpu/GrResourceCache.h
+++ b/src/gpu/GrResourceCache.h
@@ -206,6 +206,10 @@
  *  For even faster searches, a hash is computed from the Key. If there is
  *  a collision between two keys with the same hash, we fall back on the
  *  bsearch, and update the hash to reflect the most recent Key requested.
+ *
+ *  It is a goal to make the GrResourceCache the central repository and bookkeeper
+ *  of all resources. It should replace the linked list of GrResources that
+ *  GrGpu uses to call abandon/release.
  */
 class GrResourceCache {
 public: