SkPDF: move all pdf sources into src/pdf

cmake/CMakeLists.txt

Index: cmake/CMakeLists.txt
diff --git a/cmake/CMakeLists.txt b/cmake/CMakeLists.txt
index f0b0e31d91f7b9dce003af441f647cd9190bd7a5..d71415996cd4ac75f74299e3523e9977ef8136d7 100644
--- a/cmake/CMakeLists.txt
+++ b/cmake/CMakeLists.txt
@@ -204,9 +204,10 @@ endif()
 if (ZLIB_FOUND)
     list (APPEND private_includes ${ZLIB_INCLUDE_DIRS})
     list (APPEND libs             ${ZLIB_LIBRARIES})
-    remove_srcs(../src/doc/SkDocument_PDF_None.cpp)
+    remove_srcs(../src/pdf/SkDocument_PDF_None.cpp)
 else()
-    remove_srcs(../src/pdf/*.cpp ../src/doc/SkDocument_PDF.cpp)
+    remove_srcs(../src/pdf/*.cpp)
+    set (srcs ${srcs} ../src/pdf/SkDocument_PDF_None.cpp)
 endif()
 
 if (WEBP_INCLUDE_DIRS AND WEBP_LIBRARIES)