move files out of private, and fix up callers to IWYU

Realized that a pending CL needed to add (yet another) private type to SkRecords.h, but w/o this CL I'd be forced to move that header also into private. This change frees us up to not have transitive exposure for types that need to be recorded.

Bug: skia:
Change-Id: Id79f1c2e44ba85e063c1360cf96c92de6397ca2b
Reviewed-on: https://skia-review.googlesource.com/17031
Commit-Queue: Mike Reed <reed@google.com>
Reviewed-by: Mike Klein <mtklein@chromium.org>
diff --git a/tests/ImageGeneratorTest.cpp b/tests/ImageGeneratorTest.cpp
index d79b434..3d82534 100644
--- a/tests/ImageGeneratorTest.cpp
+++ b/tests/ImageGeneratorTest.cpp
@@ -6,6 +6,7 @@
  */
 
 #include "SkData.h"
+#include "SkCanvas.h"
 #include "SkGraphics.h"
 #include "SkImageGenerator.h"
 #include "Test.h"