IWYU: 'core' target, files starting A-C.

TBR=reed@google.com
Verbal lgtm, does not change API.

Committed: https://skia.googlesource.com/skia/+/7403d87db8e43d4c2b5b25ac22a0ebc22bd09d69

Review URL: https://codereview.chromium.org/1265033002
diff --git a/samplecode/SampleClipDrawMatch.cpp b/samplecode/SampleClipDrawMatch.cpp
index 6a2a37b..c79c872 100644
--- a/samplecode/SampleClipDrawMatch.cpp
+++ b/samplecode/SampleClipDrawMatch.cpp
@@ -8,6 +8,8 @@
 #include "SampleCode.h"
 #include "SkCanvas.h"
 #include "SkInterpolator.h"
+#include "SkPath.h"
+#include "SkRRect.h"
 #include "SkTime.h"
 
 // This slide tests out the match up between BW clipping and rendering. It can