make tests portable by using 565 compatible colors

TBR=reed@google.com

Review URL: https://codereview.chromium.org/1262703002
diff --git a/gm/imagefilterscropexpand.cpp b/gm/imagefilterscropexpand.cpp
index 4fe746a..8f90fb1 100644
--- a/gm/imagefilterscropexpand.cpp
+++ b/gm/imagefilterscropexpand.cpp
@@ -41,9 +41,9 @@
         SkCanvas canvas(*bitmap);
         canvas.clear(0xFFFF0000);
         SkPaint darkPaint;
-        darkPaint.setColor(0xFF404040);
+        darkPaint.setColor(sk_tool_utils::color_to_565(0xFF404040));
         SkPaint lightPaint;
-        lightPaint.setColor(0xFFA0A0A0);
+        lightPaint.setColor(sk_tool_utils::color_to_565(0xFFA0A0A0));
         for (int y = 8; y < 48; y += 16) {
             for (int x = 8; x < 48; x += 16) {
                 canvas.save();