add portable and canonical font support for DM

gm/tilemodes.cpp

Index: gm/tilemodes.cpp
diff --git a/gm/tilemodes.cpp b/gm/tilemodes.cpp
index 99d3a4708b1c48c3a51467468a87c19b3b7d058c..a912cba5e7690037ee33c9bb78c322f4c0a28128 100644
--- a/gm/tilemodes.cpp
+++ b/gm/tilemodes.cpp
@@ -100,6 +100,7 @@ protected:
                 SkPaint p;
                 SkString str;
                 p.setAntiAlias(true);
+                sk_tool_utils::set_portable_typeface(&p);
                 p.setDither(true);
                 str.printf("[%s,%s]", gModeNames[kx], gModeNames[ky]);
 
@@ -139,6 +140,7 @@ protected:
                     SkPaint p;
                     SkString str;
                     p.setAntiAlias(true);
+                    sk_tool_utils::set_portable_typeface(&p);
                     str.printf("%s, %s", gConfigNames[i], gFilterNames[j]);
                     canvas->drawText(str.c_str(), str.size(), x, y + r.height() * 2 / 3, p);
                 }
@@ -221,6 +223,7 @@ protected:
 
         SkPaint p;
         p.setAntiAlias(true);
+        sk_tool_utils::set_portable_typeface(&p);
         p.setTextAlign(SkPaint::kCenter_Align);
 
         for (size_t kx = 0; kx < SK_ARRAY_COUNT(gModes); kx++) {