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/sksl/SkSLHCodeGenerator.cpp b/src/sksl/SkSLHCodeGenerator.cpp
index 7127415..f43aa17 100644
--- a/src/sksl/SkSLHCodeGenerator.cpp
+++ b/src/sksl/SkSLHCodeGenerator.cpp
@@ -5,15 +5,15 @@
  * found in the LICENSE file.
  */
 
-#include "SkSLHCodeGenerator.h"
+#include "src/sksl/SkSLHCodeGenerator.h"
 
-#include "SkSLParser.h"
-#include "SkSLUtil.h"
-#include "ir/SkSLEnum.h"
-#include "ir/SkSLFunctionDeclaration.h"
-#include "ir/SkSLFunctionDefinition.h"
-#include "ir/SkSLSection.h"
-#include "ir/SkSLVarDeclarations.h"
+#include "src/sksl/SkSLParser.h"
+#include "src/sksl/SkSLUtil.h"
+#include "src/sksl/ir/SkSLEnum.h"
+#include "src/sksl/ir/SkSLFunctionDeclaration.h"
+#include "src/sksl/ir/SkSLFunctionDefinition.h"
+#include "src/sksl/ir/SkSLSection.h"
+#include "src/sksl/ir/SkSLVarDeclarations.h"
 
 #include <set>
 
@@ -342,10 +342,11 @@
                  "#define %s_DEFINED\n",
                  fFullName.c_str(),
                  fFullName.c_str());
-    this->writef("#include \"SkTypes.h\"\n");
+    this->writef("#include \"include/core/SkTypes.h\"\n");
     this->writeSection(HEADER_SECTION);
-    this->writef("#include \"GrFragmentProcessor.h\"\n"
-                 "#include \"GrCoordTransform.h\"\n");
+    this->writef("\n"
+                 "#include \"src/gpu/GrCoordTransform.h\"\n"
+                 "#include \"src/gpu/GrFragmentProcessor.h\"\n");
     this->writef("class %s : public GrFragmentProcessor {\n"
                  "public:\n",
                  fFullName.c_str());