Fix gyp_v8 to work with use_system_icu=1

Makefile

 # Copyright 2012 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
 #       disclaimer in the documentation and/or other materials provided
@@ skipping 334 matching lines @@
 native.clean:
         rm -f $(OUTDIR)/Makefile.native
         rm -rf $(OUTDIR)/native
         find $(OUTDIR) -regex '.*\(host\|target\).native\.mk' -delete
 
 clean: $(addsuffix .clean, $(ARCHES) $(ANDROID_ARCHES) $(NACL_ARCHES)) native.clean
 
 # GYP file generation targets.
 OUT_MAKEFILES = $(addprefix $(OUTDIR)/Makefile.,$(ARCHES))
 $(OUT_MAKEFILES): $(GYPFILES) $(ENVFILE)
+        PYTHONPATH="$(shell pwd)/tools/generate_shim_headers:$(PYTHONPATH)" \
         GYP_GENERATORS=make \
         build/gyp/gyp --generator-output="$(OUTDIR)" build/all.gyp \
                       -Ibuild/standalone.gypi --depth=. \
                       -Dv8_target_arch=$(subst .,,$(suffix $@)) \
                       -S.$(subst .,,$(suffix $@)) $(GYPFLAGS)
 
 $(OUTDIR)/Makefile.native: $(GYPFILES) $(ENVFILE)
+        PYTHONPATH="$(shell pwd)/tools/generate_shim_headers:$(PYTHONPATH)" \
         GYP_GENERATORS=make \
         build/gyp/gyp --generator-output="$(OUTDIR)" build/all.gyp \
                       -Ibuild/standalone.gypi --depth=. -S.native $(GYPFLAGS)
 
 must-set-ANDROID_NDK_ROOT_OR_TOOLCHAIN:
 ifndef ANDROID_NDK_ROOT
 ifndef ANDROID_TOOLCHAIN
           $(error ANDROID_NDK_ROOT or ANDROID_TOOLCHAIN must be set))
 endif
 endif
@@ skipping 23 matching lines @@
             echo "CXX=$(CXX)" >> $(ENVFILE).new
 
 # Dependencies.
 # Remember to keep these in sync with the DEPS file.
 dependencies:
         svn checkout --force http://gyp.googlecode.com/svn/trunk build/gyp \
             --revision 1656
         svn checkout --force \
             https://src.chromium.org/chrome/trunk/deps/third_party/icu46 \
             third_party/icu --revision 210659