Fixed warnings for casting large type to smaller one.

Change-Id: Ib3e2661d0383bf154bc9178dac070dfd910a393c
Reviewed-on: https://skia-review.googlesource.com/115200
Reviewed-by: Mike Klein <mtklein@google.com>
Commit-Queue: Mike Klein <mtklein@google.com>
diff --git a/include/private/SkPathRef.h b/include/private/SkPathRef.h
index b9b52d4..77d031f 100644
--- a/include/private/SkPathRef.h
+++ b/include/private/SkPathRef.h
@@ -495,13 +495,13 @@
     void setIsOval(bool isOval, bool isCCW, unsigned start) {
         fIsOval = isOval;
         fRRectOrOvalIsCCW = isCCW;
-        fRRectOrOvalStartIdx = start;
+        fRRectOrOvalStartIdx = SkToU8(start);
     }
 
     void setIsRRect(bool isRRect, bool isCCW, unsigned start) {
         fIsRRect = isRRect;
         fRRectOrOvalIsCCW = isCCW;
-        fRRectOrOvalStartIdx = start;
+        fRRectOrOvalStartIdx = SkToU8(start);
     }
 
     // called only by the editor. Note that this is not a const function.