Revert of IWYU: 'core' target, files starting A-C. (patchset #5 id:80001 of https://codereview.chromium.org/1265033002/ )

Reason for revert:
revert to unblock DEPS roll

../../chrome/browser/chromeos/display/overscan_calibrator.cc:43:10: error: variable has incomplete type 'SkPath'
  SkPath base_path;

Original issue's description:
> IWYU: 'core' target, files starting A-C.
>
> TBR=reed@google.com
> Verbal lgtm, does not change API.
>
> Committed: https://skia.googlesource.com/skia/+/7403d87db8e43d4c2b5b25ac22a0ebc22bd09d69

TBR=reed@google.com,mtklein@google.com,bungeman@google.com
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review URL: https://codereview.chromium.org/1273613002
diff --git a/gm/skbug1719.cpp b/gm/skbug1719.cpp
index 0a75d35..6652629 100644
--- a/gm/skbug1719.cpp
+++ b/gm/skbug1719.cpp
@@ -6,9 +6,8 @@
  */
 
 #include "gm.h"
-#include "SkBlurMaskFilter.h"
 #include "SkColorFilter.h"
-#include "SkPath.h"
+#include "SkBlurMaskFilter.h"
 
 namespace skiagm {