Adds tls_edit utility which patches irt_core.nexe's TLS usage.

src/untrusted/irt/irt.gyp

Index: src/untrusted/irt/irt.gyp
diff --git a/src/untrusted/irt/irt.gyp b/src/untrusted/irt/irt.gyp
index ef24b3f01900aab554a84835bb12d2ce54fefbc9..d62cc53918dbcc91653aa728d91210ee2fbc3e4a 100644
--- a/src/untrusted/irt/irt.gyp
+++ b/src/untrusted/irt/irt.gyp
@@ -52,10 +52,22 @@
   },
   'targets': [
     {
-      'target_name': 'irt_core_nexe',
+      'target_name': 'tls_edit',
+      'type': 'executable',
+      'toolsets': ['host'],
+      'sources': [
+        'tls_edit.c',
+      ],
+      'dependencies': [
+        '<(DEPTH)/native_client/src/shared/platform/platform.gyp:platform',
+        '<(DEPTH)/native_client/src/trusted/validator_ragel/rdfa_validator.gyp:rdfa_validator',
+      ],
+    },
+    {
+      'target_name': 'irt_core_raw_nexe',
       'type': 'none',
       'variables': {
-        'nexe_target': 'irt_core',
+        'nexe_target': 'irt_core_raw',
         'build_glibc': 0,
         'build_newlib': 0,
         'build_irt': 1,
@@ -68,14 +80,6 @@
         '-lgio',
         '-lm',
       ],
-      'conditions': [
-        # See comment in native_client/src/untrusted/irt/nacl.scons
-        # regarding -Ttext-segment.
-        ['target_arch=="arm"', {
-          'sources': ['<@(irt_sources)',
-                      'aeabi_read_tp.S'],
-        }],
-      ],
       'dependencies': [
         '<(DEPTH)/native_client/src/shared/gio/gio.gyp:gio_lib',
         '<(DEPTH)/native_client/src/shared/platform/platform.gyp:platform_lib',
@@ -86,6 +90,63 @@
       ],
     },
     {
+      'target_name': 'irt_core_nexe',
+      'type': 'none',
+      'dependencies': [
+        'irt_core_raw_nexe',
+        'tls_edit#host',
+      ],
+      'conditions': [
+        ['target_arch=="arm"', {
+          'actions': [
+            {
+              'action_name': 'tls_edit_irt_arm',
+              'message': 'Patching TLS for irt_core (arm)',
+              'msvs_cygwin_shell': 0,
+              'inputs': [
+                '<(PRODUCT_DIR)/tls_edit',
+                '<(PRODUCT_DIR)/irt_core_raw_newlib_arm.nexe',
+              ],
+              'outputs': [
+                '<(PRODUCT_DIR)/irt_core_newlib_arm.nexe',
+              ],
+              'action': ['<@(_inputs)', '<@(_outputs)'],
+            },
+          ],
+        }],
+        ['target_arch!="arm"', {
+          'actions': [
+            {
+              'action_name': 'tls_edit_irt_x64',
+              'message': 'Patching TLS for irt_core (x86-64)',
+              'msvs_cygwin_shell': 0,
+              'inputs': [
+                '<(PRODUCT_DIR)/tls_edit',
+                '<(PRODUCT_DIR)/irt_core_raw_newlib_x64.nexe',
+              ],
+              'outputs': [
+                '<(PRODUCT_DIR)/irt_core_newlib_x64.nexe',
+              ],
+              'action': ['<@(_inputs)', '<@(_outputs)'],
+            },
+            {
+              'action_name': 'tls_edit_irt_x32',
+              'message': 'Patching TLS for irt_core (x86-32)',
+              'msvs_cygwin_shell': 0,
+              'inputs': [
+                '<(PRODUCT_DIR)/tls_edit',
+                '<(PRODUCT_DIR)/irt_core_raw_newlib_x32.nexe',
+              ],
+              'outputs': [
+                '<(PRODUCT_DIR)/irt_core_newlib_x32.nexe',
+              ],
+              'action': ['<@(_inputs)', '<@(_outputs)'],
+            },
+          ],
+        }],
+      ],
+    },
+    {
       'target_name': 'irt_browser_lib',
       'type': 'none',
       'variables': {