rewrite includes to not need so much -Ifoo

Current strategy: everything from the top

Things to look at first are the manual changes:

   - added tools/rewrite_includes.py
   - removed -Idirectives from BUILD.gn
   - various compile.sh simplifications
   - tweak tools/embed_resources.py
   - update gn/find_headers.py to write paths from the top
   - update gn/gn_to_bp.py SkUserConfig.h layout
     so that #include "include/config/SkUserConfig.h" always
     gets the header we want.

No-Presubmit: true
Change-Id: I73a4b181654e0e38d229bc456c0d0854bae3363e
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/209706
Commit-Queue: Mike Klein <mtklein@google.com>
Reviewed-by: Hal Canary <halcanary@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
Reviewed-by: Florin Malita <fmalita@chromium.org>
diff --git a/tests/PathOpsCubicReduceOrderTest.cpp b/tests/PathOpsCubicReduceOrderTest.cpp
index 89a263c..b3d4ef9 100644
--- a/tests/PathOpsCubicReduceOrderTest.cpp
+++ b/tests/PathOpsCubicReduceOrderTest.cpp
@@ -4,13 +4,13 @@
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
-#include "PathOpsCubicIntersectionTestData.h"
-#include "PathOpsQuadIntersectionTestData.h"
-#include "PathOpsTestCommon.h"
-#include "SkIntersections.h"
-#include "SkPathOpsRect.h"
-#include "SkReduceOrder.h"
-#include "Test.h"
+#include "src/pathops/SkIntersections.h"
+#include "src/pathops/SkPathOpsRect.h"
+#include "src/pathops/SkReduceOrder.h"
+#include "tests/PathOpsCubicIntersectionTestData.h"
+#include "tests/PathOpsQuadIntersectionTestData.h"
+#include "tests/PathOpsTestCommon.h"
+#include "tests/Test.h"
 
 #if 0 // disable test until stroke reduction is supported
 static bool controls_inside(const SkDCubic& cubic) {