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/images/SkImageDecoder_libwebp.cpp b/src/images/SkImageDecoder_libwebp.cpp
index 625e96e..8bb716b 100644
--- a/src/images/SkImageDecoder_libwebp.cpp
+++ b/src/images/SkImageDecoder_libwebp.cpp
@@ -242,7 +242,7 @@
 
     config->output.colorspace = mode;
     config->output.u.RGBA.rgba = (uint8_t*)decodedBitmap->getPixels();
-    config->output.u.RGBA.stride = decodedBitmap->rowBytes();
+    config->output.u.RGBA.stride = (int) decodedBitmap->rowBytes();
     config->output.u.RGBA.size = decodedBitmap->getSize();
     config->output.is_external_memory = 1;