Improved Makefile.android's readability a bit.

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 20 matching lines @@
 
 # Generates all combinations of ANDROID ARCHES and MODES,
 # e.g. "android_ia32.release" or "android_arm.release"
 ANDROID_BUILDS = $(foreach mode,$(MODES), \
                    $(addsuffix .$(mode),$(ANDROID_ARCHES)))
 
 HOST_OS = $(shell uname -s | sed -e 's/Linux/linux/;s/Darwin/mac/')
 ANDROID_NDK_HOST_ARCH ?= $(shell uname -m | sed -e 's/i[3456]86/x86/')
 ifeq ($(HOST_OS), linux)
   TOOLCHAIN_DIR = linux-$(ANDROID_NDK_HOST_ARCH)
+else ifeq ($(HOST_OS), mac)
+  TOOLCHAIN_DIR = darwin-$(ANDROID_NDK_HOST_ARCH)
 else
-  ifeq ($(HOST_OS), mac)
-    TOOLCHAIN_DIR = darwin-$(ANDROID_NDK_HOST_ARCH)
-  else
-    $(error Host platform "${HOST_OS}" is not supported)
-  endif
+  $(error Host platform "${HOST_OS}" is not supported)
 endif
 
 ifeq ($(ARCH), android_arm)
   DEFINES  = target_arch=arm v8_target_arch=arm android_target_arch=arm android_target_platform=14
   DEFINES += arm_neon=0 arm_version=7
   TOOLCHAIN_ARCH = arm-linux-androideabi
   TOOLCHAIN_PREFIX = $(TOOLCHAIN_ARCH)
   TOOLCHAIN_VER = 4.8
+else ifeq ($(ARCH), android_arm64)
+  DEFINES  = target_arch=arm64 v8_target_arch=arm64 android_target_arch=arm64 android_target_platform=L
+  TOOLCHAIN_ARCH = aarch64-linux-android
+  TOOLCHAIN_PREFIX = $(TOOLCHAIN_ARCH)
+  TOOLCHAIN_VER = 4.9
+else ifeq ($(ARCH), android_mipsel)
+  DEFINES  = target_arch=mipsel v8_target_arch=mipsel android_target_platform=14
+  DEFINES += android_target_arch=mips mips_arch_variant=mips32r2
+  TOOLCHAIN_ARCH = mipsel-linux-android
+  TOOLCHAIN_PREFIX = $(TOOLCHAIN_ARCH)
+  TOOLCHAIN_VER = 4.8
+else ifeq ($(ARCH), android_ia32)
+  DEFINES = target_arch=ia32 v8_target_arch=ia32 android_target_arch=x86 android_target_platform=14
+  TOOLCHAIN_ARCH = x86
+  TOOLCHAIN_PREFIX = i686-linux-android
+  TOOLCHAIN_VER = 4.8
+else ifeq ($(ARCH), android_x87)
+  DEFINES = target_arch=x87 v8_target_arch=x87 android_target_arch=x86 android_target_platform=14
+  TOOLCHAIN_ARCH = x86
+  TOOLCHAIN_PREFIX = i686-linux-android
+  TOOLCHAIN_VER = 4.8
 else
-  ifeq ($(ARCH), android_arm64)
-    DEFINES  = target_arch=arm64 v8_target_arch=arm64 android_target_arch=arm64 android_target_platform=L
-    TOOLCHAIN_ARCH = aarch64-linux-android
-    TOOLCHAIN_PREFIX = $(TOOLCHAIN_ARCH)
-    TOOLCHAIN_VER = 4.9
-  else
-    ifeq ($(ARCH), android_mipsel)
-      DEFINES  = target_arch=mipsel v8_target_arch=mipsel android_target_platform=14
-      DEFINES += android_target_arch=mips mips_arch_variant=mips32r2
-      TOOLCHAIN_ARCH = mipsel-linux-android
-      TOOLCHAIN_PREFIX = $(TOOLCHAIN_ARCH)
-      TOOLCHAIN_VER = 4.8
-
-    else
-      ifeq ($(ARCH), android_ia32)
-        DEFINES = target_arch=ia32 v8_target_arch=ia32 android_target_arch=x86 android_target_platform=14
-        TOOLCHAIN_ARCH = x86
-        TOOLCHAIN_PREFIX = i686-linux-android
-        TOOLCHAIN_VER = 4.8
-      else
-        ifeq ($(ARCH), android_x87)
-          DEFINES = target_arch=x87 v8_target_arch=x87 android_target_arch=x86 android_target_platform=14
-          TOOLCHAIN_ARCH = x86
-          TOOLCHAIN_PREFIX = i686-linux-android
-          TOOLCHAIN_VER = 4.8
-        else
-          $(error Target architecture "${ARCH}" is not supported)
-        endif
-      endif
-    endif
-  endif
+  $(error Target architecture "${ARCH}" is not supported)
 endif
 
 TOOLCHAIN_PATH = \
     ${ANDROID_NDK_ROOT}/toolchains/${TOOLCHAIN_ARCH}-${TOOLCHAIN_VER}/prebuilt
 ANDROID_TOOLCHAIN ?= ${TOOLCHAIN_PATH}/${TOOLCHAIN_DIR}
 
 ifeq ($(wildcard $(ANDROID_TOOLCHAIN)),)
   $(error Cannot find Android toolchain in "${ANDROID_TOOLCHAIN}".  Please \
           check that ANDROID_NDK_ROOT and ANDROID_NDK_HOST_ARCH are set    \
           correctly)
@@ skipping 20 matching lines @@
 ANDROID_MAKEFILES = $(addprefix $(OUTDIR)/Makefile.,$(ANDROID_BUILDS))
 $(ANDROID_MAKEFILES):
         GYP_GENERATORS=make-android \
         GYP_DEFINES="${DEFINES}" \
         CC="${ANDROID_TOOLCHAIN}/bin/${TOOLCHAIN_PREFIX}-gcc" \
         CXX="${ANDROID_TOOLCHAIN}/bin/${TOOLCHAIN_PREFIX}-g++" \
         PYTHONPATH="$(shell pwd)/tools/generate_shim_headers:$(shell pwd)/build:$(PYTHONPATH)" \
         build/gyp/gyp --generator-output="${OUTDIR}" build/all.gyp \
                       -Ibuild/standalone.gypi --depth=. -Ibuild/android.gypi \
                       -S$(suffix $(basename $@))$(suffix $@) ${GYPFLAGS}