ARM64: Enable PIE on Android.

build/android.gypi

 # 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 197 matching lines @@
           ['target_arch=="mipsel"', {
             # The mips toolchain currently has problems with stack-protector.
             'cflags!': [
               '-fstack-protector',
               '-U__linux__'
             ],
             'cflags': [
               '-fno-stack-protector',
             ],
           }],
+          ['target_arch=="arm64" or target_arch=="x64"', {
+            # TODO(ulan): Enable PIE for other architectures (crbug.com/373219).
+            'cflags': [
+              '-fPIE',
+            ],
+            'ldflags': [
+              '-pie',
+            ],
+          }],
         ],
         'target_conditions': [
           ['_type=="executable"', {
             'conditions': [
               ['target_arch=="arm64"', {
                 'ldflags': [
                   '-Wl,-dynamic-linker,/system/bin/linker64',
                 ],
               }, {
                 'ldflags': [
@@ skipping 41 matching lines @@
         'ldflags!': [
           '-Wl,-z,noexecstack',
           '-Wl,--gc-sections',
           '-Wl,-O1',
           '-Wl,--as-needed',
         ],
       }],
     ],  # target_conditions
   },  # target_defaults
 }