[build] Fix d8-for-Android builds

Makefile.android

 # 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 48 matching lines @@
 else
   $(error Target architecture "${ARCH}" is not supported)
 endif
 
 # Common flags.
 DEFINES += OS=android
 
 .SECONDEXPANSION:
 $(ANDROID_BUILDS): $(OUTDIR)/Makefile.$$@
         @$(MAKE) -C "$(OUTDIR)" -f Makefile.$@ \
-                  AR="$(ANDROID_TOOLCHAIN)/ar" \

[Jakob Kummerow, 2016/05/20 09:44:15]

Dropping this line fixes:

/bin/sh:
/toolchains/arm-linux-androideabi-4.9/prebuilt/linux-x86_64/arm-linux-androideabi/bin/ar:
No such file or directory

[Jarin, 2016/05/20 10:04:53]

So why do not need to compute the ANDROID_TOOLCHAIN variable above?

[Jakob Kummerow, 2016/05/20 11:34:45]

Good point. Dropped.

                   BUILDTYPE=$(shell echo $(subst .,,$(suffix $@)) | \
                               python -c "print raw_input().capitalize()") \
                   builddir="$(shell pwd)/$(OUTDIR)/$@"
 
 # Android GYP file generation targets.
 ANDROID_MAKEFILES = $(addprefix $(OUTDIR)/Makefile.,$(ANDROID_BUILDS))
 $(ANDROID_MAKEFILES):
         GYP_GENERATORS=make-android \
         GYP_DEFINES="${DEFINES}" \
-        PYTHONPATH="$(shell pwd)/tools/generate_shim_headers:$(shell pwd)/build:$(PYTHONPATH)" \
+        PYTHONPATH="$(shell pwd)/tools/generate_shim_headers:$(shell pwd)/gypfiles:$(PYTHONPATH)" \

[Jakob Kummerow, 2016/05/20 09:44:15]

This fixes:

gyp: Error importing pymod_do_mainmodule (has_valgrind): No module named
has_valgrind

         tools/gyp/gyp --generator-output="${OUTDIR}" gypfiles/all.gyp \
                       -Igypfiles/standalone.gypi --depth=. \
                       -S$(suffix $(basename $@))$(suffix $@) ${GYPFLAGS}