IPC fuzzer child process component

build/common.gypi

Index: build/common.gypi
diff --git a/build/common.gypi b/build/common.gypi
index f4c01f579d2ac9e3f08e41c1766980e826e31399..95efe48eb92352c2f8926db37f253026c0517613 100644
--- a/build/common.gypi
+++ b/build/common.gypi
@@ -730,6 +730,9 @@
       'google_api_key%': '',
       'google_default_client_id%': '',
       'google_default_client_secret%': '',
+
+      # IPC fuzzer is disabled by default.
+      'enable_ipc_fuzzer%': 0,
     },
 
     # Copy conditionally-set variables out one scope.
@@ -1096,6 +1099,8 @@
     # MDNS is disabled by default.
     'enable_mdns%' : 0,
 
+    'enable_ipc_fuzzer%': '<(enable_ipc_fuzzer)',
+
     'conditions': [
       # The version of GCC in use, set later in platforms that use GCC and have
       # not explicitly chosen to build with clang. Currently, this means all
@@ -2248,7 +2253,10 @@
       }],
       ['enable_mdns==1', {
         'defines': ['ENABLE_MDNS=1'],
-      }]
+      }],
+      ['enable_ipc_fuzzer==1', {
+        'defines': ['ENABLE_IPC_FUZZER=1'],
+      }],
     ],  # conditions for 'target_defaults'
     'target_conditions': [
       ['enable_wexit_time_destructors==1', {