Update //third_party/protobuf to version 3.

build/common.gypi

Index: build/common.gypi
diff --git a/build/common.gypi b/build/common.gypi
index 154997656d89bf91613fbf5022c1cfde15c77423..888a6d67b49ac708bcdf3090c235d1bee0362296 100644
--- a/build/common.gypi
+++ b/build/common.gypi
@@ -2844,13 +2844,6 @@
       ['OS=="win"', {
         'defines': ['NO_TCMALLOC'],
       }],
-      ['asan==1', {
-        'defines': [
-          'ADDRESS_SANITIZER',
-          'MEMORY_TOOL_REPLACES_ALLOCATOR',
-          'MEMORY_SANITIZER_INITIAL_SIZE',
-        ],
-      }],
       ['syzyasan==1', {
         # SyzyAsan needs /PROFILE turned on to produce appropriate pdbs.
         'msvs_settings': {
@@ -3078,6 +3071,13 @@
       ['<(chromeos)==1 and >(nacl_untrusted_build)==0', {
         'defines': ['OS_CHROMEOS=1'],
       }],
+      ['<(asan)==1 and >(nacl_untrusted_build)==0', {
+        'defines': [
+          'ADDRESS_SANITIZER',
+          'MEMORY_TOOL_REPLACES_ALLOCATOR',
+          'MEMORY_SANITIZER_INITIAL_SIZE',
+        ],
+      }],
       ['enable_wexit_time_destructors==1 and OS!="win"', {
         # TODO: Enable on Windows too, http://crbug.com/404525
         'variables': { 'clang_warning_flags': ['-Wexit-time-destructors']},