Remove GrRefCnt.h in favor of SkRefCnt.h

This removes GrRefCnt.h with all its tyepdefs and #defines and just switch them
to the Sk* equivalents.

GrSafeSetNull was promoted to SkSafeSetNull in SkRefCnt.h.

BUG=None
TEST=none, no functional changes.
R=bsalomon@google.com, robertphillips@google.com

Author: tfarina@chromium.org

Review URL: https://chromiumcodereview.appspot.com/23904003

git-svn-id: http://skia.googlecode.com/svn/trunk@11151 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/tests/ClipCacheTest.cpp b/tests/ClipCacheTest.cpp
index c3801d7..9407688 100644
--- a/tests/ClipCacheTest.cpp
+++ b/tests/ClipCacheTest.cpp
@@ -58,7 +58,7 @@
         return;
     }
 
-    GrAutoUnref au(texture);
+    SkAutoUnref au(texture);
 
     SkIRect intScreen = SkIRect::MakeWH(kXSize, kYSize);
     SkRect screen;