Forward declare SkStrokeRec in SkPathEffect

Review URL: https://codereview.chromium.org/1312163008
diff --git a/tests/DrawPathTest.cpp b/tests/DrawPathTest.cpp
index 4351faf..e5d50d3 100644
--- a/tests/DrawPathTest.cpp
+++ b/tests/DrawPathTest.cpp
@@ -8,6 +8,7 @@
 #include "SkBitmap.h"
 #include "SkCanvas.h"
 #include "SkDashPathEffect.h"
+#include "SkStrokeRec.h"
 #include "SkSurface.h"
 #include "Test.h"