Fixed signed/unsigned comparison warnings in empty path gm/sample



git-svn-id: http://skia.googlecode.com/svn/trunk@2439 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/samplecode/SampleEmptyPath.cpp b/samplecode/SampleEmptyPath.cpp
index 5c865c6..cffe6cf 100644
--- a/samplecode/SampleEmptyPath.cpp
+++ b/samplecode/SampleEmptyPath.cpp
@@ -79,8 +79,8 @@
         canvas->save();
         canvas->translate(80 * SK_Scalar1, 0);
         canvas->save();
-        for (int style = 0; style < SK_ARRAY_COUNT(gStyles); ++style) {
-            for (int fill = 0; fill < SK_ARRAY_COUNT(gFills); ++fill) {
+        for (size_t style = 0; style < SK_ARRAY_COUNT(gStyles); ++style) {
+            for (size_t fill = 0; fill < SK_ARRAY_COUNT(gFills); ++fill) {
                 if (0 == i % 4) {
                     canvas->restore();
                     canvas->translate(0, rect.height() + 50 * SK_Scalar1);