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/src/gpu/gl/GrGLBuffer.h b/src/gpu/gl/GrGLBuffer.h
index 76d902c..d408e46 100644
--- a/src/gpu/gl/GrGLBuffer.h
+++ b/src/gpu/gl/GrGLBuffer.h
@@ -8,8 +8,8 @@
 #ifndef GrGLBuffer_DEFINED
 #define GrGLBuffer_DEFINED
 
-#include "GrGpuBuffer.h"
-#include "gl/GrGLTypes.h"
+#include "include/gpu/gl/GrGLTypes.h"
+#include "src/gpu/GrGpuBuffer.h"
 
 class GrGLGpu;
 class GrGLCaps;