Second wave of Win64 warning cleanup

https://codereview.chromium.org/27343002/



git-svn-id: http://skia.googlecode.com/svn/trunk@11778 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/pdf/SkPDFResourceDict.cpp b/src/pdf/SkPDFResourceDict.cpp
index 0102b3c..6f5d167 100644
--- a/src/pdf/SkPDFResourceDict.cpp
+++ b/src/pdf/SkPDFResourceDict.cpp
@@ -65,7 +65,7 @@
 
     // Actual sub-dicts will be lazily added later
     fTypes.setCount(kResourceTypeCount);
-    for (size_t i=0; i < kResourceTypeCount; i++) {
+    for (int i=0; i < kResourceTypeCount; i++) {
         fTypes[i] = NULL;
     }
 }