IWYU

fissioned from https://skia-review.googlesource.com/c/skia/+/185460

Bug: skia:
Change-Id: I92857df460ffec402101bfa4c90678db889ea9c5
Reviewed-on: https://skia-review.googlesource.com/c/185697
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Reed <reed@google.com>
Auto-Submit: Mike Reed <reed@google.com>
diff --git a/samplecode/SampleRegion.cpp b/samplecode/SampleRegion.cpp
index 2ae5f87..c5eaf00 100644
--- a/samplecode/SampleRegion.cpp
+++ b/samplecode/SampleRegion.cpp
@@ -9,6 +9,7 @@
 #include "SkBitmap.h"
 #include "SkCanvas.h"
 #include "SkFont.h"
+#include "SkFontMetrics.h"
 #include "SkGradientShader.h"
 #include "SkPath.h"
 #include "SkRegion.h"