Fix all relative includes to third_party.

third_party/BUILD.gn

 # Copyright 2014 PDFium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 group("third_party") {
   deps = [
     ":bigint",
     ":fx_freetype",
     ":pdfium_base",
   ]
@@ skipping 28 matching lines @@
   }
 }
 
 # Tests may link against this even if the production library doesn't,
 # so it needs to be separate from it.
 static_library("fx_freetype") {
   configs -= [ "//build/config/compiler:chromium_code" ]
   configs += [
     "//build/config/compiler:no_chromium_code",
     "//third_party/pdfium:pdfium_config",
+
     # Must be after no_chromium_code for warning flags to be ordered correctly.
     ":fx_freetype_warnings",
   ]
   defines = [ "FT2_BUILD_LIBRARY" ]
   sources = [
     "freetype/include/freetype/freetype.h",
     "freetype/include/freetype/ftmm.h",
     "freetype/include/freetype/ftotval.h",
     "freetype/include/freetype/ftoutln.h",
     "freetype/include/freetype/internal/ftobjs.h",
@@ skipping 30 matching lines @@
     # calc_butt_cap() in agg_vcgen_stroke.cpp is unused.
     cflags = [ "-Wno-unused-function" ]
   }
 }
 
 source_set("fx_agg") {
   configs -= [ "//build/config/compiler:chromium_code" ]
   configs += [
     "//build/config/compiler:no_chromium_code",
     "//third_party/pdfium:pdfium_config",
+
     # Must be after no_chromium_code for warning flags to be ordered correctly.
     ":fx_agg_warnings",
   ]
   sources = [
     "agg23/agg_basics.h",
     "agg23/agg_clip_liang_barsky.h",
     "agg23/agg_conv_dash.h",
     "agg23/agg_conv_stroke.h",
     "agg23/agg_curves.cpp",
     "agg23/agg_curves.h",
     "agg23/agg_path_storage.cpp",
     "agg23/agg_path_storage.h",
     "agg23/agg_rasterizer_scanline_aa.cpp",
     "agg23/agg_rasterizer_scanline_aa.h",
     "agg23/agg_renderer_scanline.h",
     "agg23/agg_rendering_buffer.h",
     "agg23/agg_scanline_u.h",
     "agg23/agg_vcgen_dash.cpp",
     "agg23/agg_vcgen_stroke.cpp",
   ]
 }
 
 config("fx_lcms2_warnings") {
   visibility = [ ":*" ]
   if (is_clang) {
     cflags = [
       # cmslut.cc is sloppy with aggregate initialization. Version 2.7 of this
       # library doesn't appear to have this problem.
       "-Wno-missing-braces",
+
       # FindPrev() in cmsplugin.c is unused.
       "-Wno-unused-function",
     ]
   }
 }
 
 source_set("fx_lcms2") {
   configs -= [ "//build/config/compiler:chromium_code" ]
   configs += [
     "//build/config/compiler:no_chromium_code",
     "//third_party/pdfium:pdfium_config",
+
     # Must be after no_chromium_code for warning flags to be ordered correctly.
     ":fx_lcms2_warnings",
   ]
   sources = [
     "lcms2-2.6/include/lcms2.h",
     "lcms2-2.6/include/lcms2_plugin.h",
     "lcms2-2.6/src/cmscam02.c",
     "lcms2-2.6/src/cmscgats.c",
     "lcms2-2.6/src/cmscnvrt.c",
     "lcms2-2.6/src/cmserr.c",
@@ skipping 14 matching lines @@
     "lcms2-2.6/src/cmsps2.c",
     "lcms2-2.6/src/cmssamp.c",
     "lcms2-2.6/src/cmssm.c",
     "lcms2-2.6/src/cmstypes.c",
     "lcms2-2.6/src/cmsvirt.c",
     "lcms2-2.6/src/cmswtpnt.c",
     "lcms2-2.6/src/cmsxform.c",
   ]
 }
 
-source_set("fx_libjpeg") {
+# This is only used for standalone builds.
+source_set("jpeg") {
   configs -= [ "//build/config/compiler:chromium_code" ]
   configs += [
     "//build/config/compiler:no_chromium_code",
     "//third_party/pdfium:pdfium_config",
   ]
   sources = [
     "libjpeg/cderror.h",
     "libjpeg/cdjpeg.h",
     "libjpeg/fpdfapi_jcapimin.c",
     "libjpeg/fpdfapi_jcapistd.c",
@@ skipping 116 matching lines @@
     "base/macros.h",
     "base/nonstd_unique_ptr.h",
     "base/numerics/safe_conversions.h",
     "base/numerics/safe_conversions_impl.h",
     "base/numerics/safe_math.h",
     "base/numerics/safe_math_impl.h",
     "base/stl_util.h",
     "base/template_util.h",
   ]
 }